Just got this game downloaded recently, and I'm having a blast. Any protips you guys can hook me up with?
Just some class tips:
Sniper: Is your team getting stomped? Your team obviously needs a 5th sniper... do it! Be sure to stand next to the other snipers, they know what's up!
Soldier: Rocket jumping is useless and anyone who tells you otherwise is a darned, dirty liar. Moving across a map quickly and getting into unexpected positions is for noobs.
Heavy: You are teh heavy! You are INVINCIBLE!
Demoman: Demoknights (uses a shield in place of sticky grenades and focuses on melee combat) are highly valued by teams because of their versatility, lack of useless sticky grenades, and roguish good looks (If you wear a Ghastly Gibus hat you'll be sure to pick up all the chicks)
Medic: Medics are useless. I know this because no one on public servers ever plays them, so they must be bad. Don't play medic, its a scrub class.
Pyro: W + M1. Use the backburner. Frontal assaults only.
Scout: You are the counter to the engineer's sentry. See a level 3 sentry? Its your job to take it out.
Engineer: Build a level 3 sentry at spawn (anything less than a level 3 is useless!) Carry it to the battle and plop it down; it is teh sentry, it is invincible (unless of course a scout gets it!). Teleporters and dispensers are useless and it'd be a waste of time to make them... who needs teammates when you've got a sentry?
Spy: Be sure to get into disguise (scout!) as you run behind enemy lines (don't stealth because it'll use up your cloak energy).
/tongue-in-cheek
But seriously, a quick pyro tip: The detonator (one of the pyro secondary weapons) can be used to do a mini rocket jump. It won't get you as high as the soldier's rocket jump or demoman sticky jump, but it can get you up to some places too high for your normal jump, making it a good shortcut creator.
Quick spy tip: Be aware that when having the disguise menu open, the - key can be used to switch to your team's colors, allowing you to disguise as your own team. Useful in conjunction with the dead ringer.