Get a 360 dude, trust me - when i played Double Agent it was like they took the original idea and put a great spin on it - there are different endings based on what moral path you take and now Conviction is taking it further. A recent preview special i read says that you have to merge into the crowds and use the people around you as cover instead of the tradtional shadows in the other games. The AI will be so much more focused and refined and the different NPC's will have definite characteristics and motives - you will have to work out just who to trust and who to throw out of a window...tough call.
On an additional strand - i read a script review of the SC movie and by all accounts it sounds damn good. There is a lot of life in Sam Fisher yet and that can only be a good thing for the fans of this brilliant series.
Holy crap - nearly forgot - check out these books, they are really good.
http://www.amazon.co.uk/Clancys-Splinte
amp;sr=1-1
There are 3 of them and more on the way.