Beware Sam Fisher...He could be behind you, underneath you, above you, or even... in front of you...
A very good feature in SCT is the shotgun and sniper attachment, you can switch from attachment by pressing ALT and which mouse butten 2 you can shoot people brutally, but this is everything but stealth and will mostly result in a low mission succes rating.
Another very good thing about the game are the new moves you can do, you can trow people of ships and you can grab somebody from beneath.
You can interrogate nearly everybody and that's something I missed in the previous two games.
The game has ten levels which are different at style, one level you need to break into a bank and be absolutely stealth and another level you first need to listen to some conversation and then kill them, this was a hard part for me, because there bodyguards shoot right, and Sam often does not...(or me xP)
There are also missions that have timers, like when you need to stop a missile from blowing or when you need to disarm several bombs and in meantime kill people who are shooting you.
All together this game is the best in the splinter cell serie(on pc) for now and it is definitly worth to pay some money for it.
MASTERPIECE!