So the latest word on Left 4 Dead is that it is due for a late Summer release, Shacknews said this is to be August/September
BUT Turtle Rock the devs are as well now know working on Valve Time...which is notorious for being slower than real world time.
As such I forsee Left 4 Dead being kept behind until Episode 3 is ready for release, so I expect to see Episode 3 and Left 4 Dead coming out November time.
Other Shacknews stuff reports that we are due to see some new TF2 maps (Badlands remake :o ) and an overhaul of the game starting with changes to the medic.
For me, as long as they don't throw in grenades I will be happy! Anything else to keep things fresh is a-ok in my mind.