funny you mention Tom Cancly's stuff. I've been following some games, I played a very old Rainbow Six, and it was very far from being any good as very realistic, technical and tactical game, because Delta Force was beating all that.
Now the last Delta Force as fallen under the evil of modern games, and is no3w more fun than technical, and Tom Cancly's games came up the ladder as both fun and tactical.
I've played Ghost Recon Advanced Warrior or something like that, I remember being nick'ed as GRAW, and it was superb, very heavy, good tactical system, it was great to be able to control the other NPCs, even if just by pointing them where to go. Being in cover at all times, using silenced weaponry, it was fantastic, although I think this kind of games are only good for single player.
Finally, it was still technical, used some of the latest weaponry available (for the US), the story was kinda military childish, but it was fine, I just think there should have been longer single player, maybe more missions. I guess that can be fixed with some downloads from moding community or booster packs.
The system was kinda SWAT4 but more advanced, but since then, Tom Clancy's games have been beating Novalogic's Delta Force.
I just hope this COD4 is either just fun (like BF-Bad Company seems to be) or if they try it as technical, to be very technical and tactical, otherwise it will just suck.