Just played this game last night for a couple of hours since the BF2142 clan match was cancelled - have to say I am very impressed with it.
I never really played the original TF game on the HL1 engine, so TF2 is a novelty, new concept to me. I love the 'toy story' like graphics and the motion blur effects.
The concept is really strange, like 9 or 10 different totally different classes. If it was real life none of them would probably get on or chose to be friends - very wierd!
This is of course what makes the game interesting, it didn't take me long to find out what characters I was most effective with and the stats table at the end of each map helps chart your own progress.
Great game, looking forward to playing with more experienced THN people to learn more about it.