timppu: I don't see the point to fret about it. It is not like there haven't been GameBoy or Nokia Symbian mobile versions of known game series before. You can just choose to ignore them.
From what I'm gathering of the comments a lot of the negative feedback is coming from them teasing a new Deus Ex game to what is primarily a PC and console gaming audience, which got them psyched for a new PC and console Deus Ex game.
Had they just come out and announced it without having a buildup of hype that audience wouldn't be feeling so let down and it wouldn't be nearly so negative.
EDIT: yeah, what P1na said. :P