I am serious, and don't call me Shirl- ... oh.
(I really need to just save this as a Word document given the amount of times I've typed it out.)
The ending's presentation (don't care about the boss fight, not what I'm talking about) is rather workmanlike. Functionally, it's almost perfect.
The entirety of Human Revolution is a debate, and the ending asks you for your verdict (there's even an 'abstain' option), your personal belief, your philosophy. The exposition isn't meaningless, it surmises the key thoughts behind each idea, and reflects on some of the reasons for it.
It then calls into question a key theme of the game: what makes us human? You may think more or less for Adam now that he's in a position of such potential power, and that's reflected in the final conversations he has with various people, and the fact that we don't see what happens to the other characters. He's removed and distant, and everything he's found out about through the game pushes him away from them - he knows all the dirty secrets of the guys at the top that ordinary people aren't meant to know.
We don't see the repercussions of the choices because they're irrelevant. We know what eventually becomes of the world in the original Deus Ex, and showing them takes the spotlight away from what the game really wants you to think about, and what the game has all been about, which is your personal philosophy. A friend and I finished it on the same day and both picked different endings, and then talked about why we did for an hour and a half.
So yeah, narratively and thematically it's spot on, the 4 buttons could have been done better (they've said themselves they had something a little more elaborate, but time-constraints factored in), but people get far, far too hung up on them.