Kay, just beat it.
Two things.
First, the gripe. You get a shitload of ADAM at one point, but can't use it on anything.
Fuck.
Second. The ending, though it was pretty good [and pretty to boot], was far shorter than I expected of this game. But then, I suppose the intro was short too, so...maybe I should've expected something shorter. However, the "ending" before the ending...for lack of a better term [think "poke/rape" if you've seen it] was pretty epic.
Overall, I'd rate the game, probly about an 8/10. While the game was GORGEOUS and pretty fun, as well as having a pretty damned solid plot, it lacks multiplayer. This game would have EPIC MP, but no, it doesn't. So...the game as a whole, I rate 8/10. The 1P "mode", I'd probly give somewhere in the area of 9.5-9.75/10.
I finished with 42/50 acheivements btw. I don't know how the hell to get into those two rooms I missed though [one in a basement barred with lattice stuff, and one apartment thinger].