The devs driven by eidos are making the game THEY want to make there is no way in HELL, they are making it for the current fans, it's not possible in any sense.
Given that fans tend to be a bunch of overreacting dicks with fonder memories of a game that might not have been as good as they remembered*... yeah, they're not. Secondly, you make the blanket assumption that Eidos devs aren't fans of Deus Ex, and by and large, when someone puts this amount of dedication into making a game, they are.
Besides, no one makes a game for fans, because that's stupid. Fans tend, more often than not, to know nothing about game design and have worthless opinions (see: Diablo III 'shops).
I know this concept might seem revolutionary to some, so I'll go ahead and answer the question you might be asking. Why would publishers make games if they're not to appease fans? Because they're out to make money--You know, like for jobs and stuff. People like money. It's very useful. Of course, the only way to make money on a video game is to make that game a good game. If it's not a clone of the original with updated graphics, hey, that's fine, as long as it's good. If Bioshock had been a clone of System Shock 2 (actually the levels pretty much i]were clones), it's possible people might not have enjoyed it as much. Sure, the fans might have been, but Bioshock was made to be a good game, not a gift to the fans.
Game developers are not a public service--they're businesses. The only time you have any right to call developers names is if they release a game that is clearly broken (See Stalker: Clear Sky) and don't even support it.
So I mean, you can sit here and bitch about Deus Ex 3 not being Deus Ex, or you can hope that it'll be the Bioshock to your System Shock.
I will say that the cover system for the original Deus Ex is absolutely retarded. Not sure where people are getting the Gears of War comparisons. Need I remind you that Splinter Cell was third person and used cover? Gasp! Regarding health regeneration, I know most of you want to compare it to Gears of War, but come on! Didn't they say something about it being more like Call of Duty's?
The main concern I've got is that Eidos almost seems to be mashing together a good bit of everything that worked for games like Bioshock (augmentations), Metal Gear Solid (LOS + Sound), Call of Duty (Regening Health), and other stuff, as opposed to making a game based on its own merits.
*Not saying this about Deus Ex.