There is no HUD, you have a cellphone on your back that has a big ass LED on it that's either green (completely hidden), yellow (visible) or red (you better saved some ammo). One of the most disappointing aspects of the 360 version is that they simplified the classic SC gameplay too much. You get more content and more story for less money if you buy the Xbox version, not to mention better gameplay, superior level design and a decent save system. Now the good thing about the co-op campaign is that it is interconnected with the main storyline, even more so than the co-op campaign in Chaos Theory.

The Xbox version also has a full co-op campaign that you can play online or offline (2p split screen). Especially if you compare some of the levels that exist on both versions (Iceland/Prison). It is very content light in comparison to the Xbox version. I don't own the 360 version but based on what I've played (demo and full version at a retailer) and especially what I've seen in videos (basically the whole game) and read on message boards it is Splinter Cell in name only.

Splinter cell double agent pc gameplay