The Armies:
Imperial Guard:
Junior Officer
4 Guardsmen

Two infantry platoons, consisting of the following:
Platoon HQ:
Junior Officer w/ Iron Discipline
2 Guardsmen
Autocannon Team

Squad 1:
6 Guardsmen, Sergeant
Missile Launcher Team

Squad 2:
6 Guardsmen, Sergeant
Missile Launcher Team
Iron Discipline
Close Order Drill

Tau: (I think this is accurate, I don't play Tau, myself)
Shas'o w/ Ion Blaster, Plasma Rifle, shield generator, HW multi-tracker, stimulant njector, iridium armor
Crisis Team:
Shas'ui w/ Plasma Rifle, missile pod, targeting array, HW multi-tracker, Team Leader

3 squads of 6 Fire Warriors

Fast Attack:
Piranha w/ Burst Cannon, Targeting Array
The scenario:
Captain Stevens surveyed the objective, and went over his briefing again in his mind. An Imperial lander had crashed in the outskirts of the city, carrying a cargo of some vital importance. They hadn't told him what it was, only to hold the area and provide security for the salvage team when it landed. They had been fighting the Tau on this backwater world for months, and it was likely that they were in the area and would come to investigate. He only had a fraction of his company with him. 2 Platoons, that was all that they had been able to spare. All of their surviving armor was tied up elsewhere. Now the friendly lines were twelve miles behind them. Ahead of them, the wreckage was clearly discernable. The lander had come down in a wooded area, with a few scattered buildings. He cautiously ordered his men to advance. Then, he heard it - the unmistakable whine of a Piranha's engine. A Tau patrol, and close. This was about to get ugly.

The terrain:
The terrain consisted of the ruined building bits from my IG Battleforce set and the crashed lander from the Battle for Macragge boxed set, set up in a ring around the objective. We also set down some paper to mark woods and forest between the two sides. The playing area was very small; just a coffee table, really. It probably would've been better suited to a kill-team game.

The Tau deployed along the table edge in the northwest corner, the guard in the southwest. With so many troops and such a small deployment zone, we were packed pretty tight.

The Battle:
After setting up terrain we each deployed in opposite corners. The Tau rolled to go first.

Turn 1 Tau:
The two Fire Warrior teams to the east moved farther east, while the Piranha and remaining warriors went south. The Battlesuits approached the large piece of lander wreckage southeast of them.

Turn 1 IG:
"Get to that cover!", the 1st Platoon leader, Lieutenant Tovin, ordered. Sergeant Stark and his squad ran towards the small copse of trees sandwiched between the ruined buildings and the wreckage of the crashed lander. On his right, 2nd squad was doing the same, while the LT was heading towards the ruins. Behind them, 2nd Platoon was heading north to flank the Tau force, with Lt. Barak personally leading the advance.

The 2nd Platoon HQ went north, out of the safety of cover and into the line of sight of the Tau force. 2nd Platoon, 1st squad, and the company HQ squad, were right behind them. The rest of the force moved out towards cover.

Turn 2 Tau:
The Tau Piranha, and the western Fire Warrior squad continue their advance south. One of the squads to the east moved farther that way, and the Battlesuits hop onto a chunk of wreckage to get a better field of vision. The Tau battlesuits annihilate 2nd Platoon HQ, leaving no survivors. The Fire Warriors that hadn't moved shoot at 2nd Pltn, 1st Squad but luckily inflict no wounds.

Turn 2 IG:
The men of 2nd Pltn, 1st Squad watched in shock as Lt. Barak and his men left the safety of cover and were cut down by a fusillade of Plasma fire. "Take out the battlesuits!" The captain yelled; recognizing them as by far the biggest threat here. They had to be destroyed before they slaughtered another squad of Guardsmen. 1st Squad was more than happy to comply, letting lose a volley of lasgun fire that only pinged off the suit's thick armor. Unfortunately they were out of Meltagun range. 1st Squad's rocket gunner let a Krak missile fly at the lead suit. The Shas'o's last thought was "What's that sound?" as the projectile found the joint between his head and neck armor and detonated. Without the protection of the suit's armor plate, the Shas'o was almost vaporized by the explosion; reduced to a fine mist and a few larger chunks that rained down on his horrified compatriots. The Shas'ui had little time to realize what had happened as a Plasmagun shot blasted its way through his chest the next instant, killing him.

On the other side of the battlefield, Sergeant Stark and his men dove into the woods, taking cover behind the trees. In front of them, A Tau Piranha was cautiously advancing among the debris field. Stark's Meltagunner fired at it, but inflicted only minor damage.

1st Pltn moves into the forest, while 1st Pltn HQ climbs onto the second story of a ruined building, giving their autocannon a good field of fire and putting the Tau right in their sights. 2nd Pltn, 2nd squad moves into another copse of trees while the Company HQ takes cover amid the wreckage of the lander. 2nd Pltn, 1st squad stands their ground. 1st Pltn, 1st Squad gets a good hit on the Piranha with a Meltagun, but only manages to scratch the paint (rolled a 1) and rattle the crew. 2nd Pltn, 1st Squad fire at the enemy commander, and an extremely lucky Krak missile shot connects - the commander fails his 2+ armor save and is vaporized! The rest of the guardsmen open fire on the remaining battlesuit, cutting him down with a well-placed Plasmagun shot.

Turn 3 Tau:
The Piranha just sits there. The nearby Fire Warriors begin to shoot at 1st Pltn, 1st Squad but fail to hit. The rest of the Fire Warriors open up on 2nd Pltn, 2nd Squad and kill 5 Guardsmen.

Turn 3 IG:
1st Platoon watched as the Tau Piranha was hit by another blast. It exploded in a ball of fire and smashed into a ruined building, showering the battlefield with flaming debris. Sergeant Stark and his men began trading shots with the nearby Fire Warriors, killing 2 and fortunately suffering no casualties in return. Meanwhile, Captain Stevens could see that now that the only real threats had been destroyed, there was little left to do but mop up. "Leave none of them alive," he ordered 2nd Platoon; after watching the Lieutenant and his squad blasted into pieces, they were happy to get their chance at vengeance. The Fire Warriors, their crisis suits obliterated and taking heavy casualties, began to flee.

1st Pltn, 1st Squad returns fire on the nearby Warriors, killing 2. They fail their morale check. 2nd Squad targets the Piranha, getting a penetrating hit with a plasmagun and blasting it into a million pieces. 1st Pltn HQ kills 2 Fire Warriors, one with a Lasgun, one with an Autocannon shot. 2nd Pltn, 2nd Squad kills 2 more Fire Warriors in retaliation, and 1st Squad kills 3, 2 with a Frag Missile. The remaining Fire Warriors all fail their morale checks and run for their lives.

Turn 4 Tau:
The western group of Fire Warriors makes their save and comes back under control. The other 2 squads don't. That last group of Fire Warriors tries to hold against the Guard, and manages to kill 2 men from 1st Pltn, 1st Squad. They make their pinning checks.

Turn 4 IG:
"Fix Bayonets!" Sergeant Stark shouted to his men, as two of their fellow Guardsmen were shot down by the Tau warriors. "For the Emperor!" He shouted, screaming with righteous fury as he led his men out of the treeline. They smashed into the Tau squad with full force. The Tau, obviously caught by surprise at the Guardsmen's assault, offered little resistance as Stark and his men eviscerated them one by one. Meanwhile, 1st Platoon's autocannon gunner was putting round after round into the backs of the fleeing Tau warriors, smiling like a madman as the cowardly Xenos fell. Between the autocannon and 2nd Platoon's fire, there would be no survivors.

1st Pltn, 1st Squad, seriously PO'ed and hungry for revenge, runs out of the forest and charges the 4 Fire Warriors.
The 5 Tau survivors to the east are cut down by 1st Pltn's Autocannon and Frag Missiles.
1St Pltn, 1st Squad charges into the 4 survivors, and wipes them out in close combat.

Total victory for the Imperial Guard, annihilating defeat for the Tau.

I don't know much about the Tau, but I don't think this army was very well thought out. Once that Shas'o was gone, there was little hope of winning for the Tau. I knowingly sacrificed that HQ squad by putting them in the lead, thinking that another junior officer was more expendable than the squad behind it with the heavier weapons. It worked, but I was also very lucky with that missile. I guess the Emperor was looking out for me that time. If those battlesuits had stayed alive just another turn, it might have changed the course of the game. That Piranha seemed like an utterly useless waste of points. In the end, I lost 12 men, which seems like a pretty good trade for 500 points of Tau wiped off the map. I don't think the Tau really had any idea what they were trying to do, or any cohesive strategy in mind. That was definitely the quickest game I've ever played.