Really, for a while the biggest issue I had was how easy the game was for me playing on 'Give me Deus Ex', the highest difficulty. Now, my biggest problem is a lack luster ending no matter which one you pick.

Basically, you decide on the end when it comes, and it seems your actions don't affect it to much outside of a bit of dialogue. You can just save before the choice to view them all, so the multiple endings bit kind of shoots itself in the foot as there isn't much reason to replay the game for a different ending, though most people could find the gameplay itself reason enough to play again, it is quite good.

But really, smurf the endings. Everything I'm about to post is spoiling end game, so you'll want to wait to beat it before reading any of this.

(SPOILER)
First off, you don't even know what the smurf will happen. All you get is conjecture as to what might happen. I smurfing could have taken a wild smurfing guess to without the game giving me their wild smurfing guess. You really don't see ANY of your actions effects. Nothing. smurfing zilch.

In addition, if you go the Route of the Illuminati guy, I forget his name of the top of my head, they actually have the smurfing balls to use a quote from Albert Einstien to try to make technology sound bad and evil. They don't even hide it, they straight up tell you it was smurfing Albert Einstein.

Sersiously Deus Ex Ending, smurf you.