It would seem that Team Fortress 2 is updating the game with .. a new class?!  Some details below the cut.

The Guard Dog doesn’t appear to be a terribly offensive class – boasting only a double-firing, triple machine gun that looks scarier than it really is, and a rocket-boosted melee attack. It CAN, however, carry and steal medpacks, ammunition and guns from both the ground and the enemy, so that could be interesting. Sealing the deal is its ability to sniff out dead people: if the Guard Dog sniffs an intact enemy corpse, then it can “track the exact position” of an enemy – even if they’re stealthed, changed classes, or are a disguised spy! Should be an interesting shift in group dynamics if nothing else.

OH AND ALSO:

The dog can piss into the Sniper’s Jarate [read: urine to throw at people] Jar!  Awesome.