I still have not finished Deus Ex: Human Revolution... but I do feel an urge to participate, as in NOW. The first responses to OP's post were quite surprisingly negative and unreflected, especially for a forum that usually seems to like it nice and clean and entertaining, wielding an unforgiving banhammer in the most righteous manner imaginable.
So I went on playing Deus Ex: HR, thinking I'd come back here once I'd finished it.
Then it happened... I don't know what exactly, I wasn't upset or annoyed by anything very specific in particular. I just got somewhat bored and annoyed. I just couldn't bring myself to play it anymore, for a whole week already now.
So, I still haven't finished it. But what I did - and that amazes me more - is this: I dug up the old Deus Ex, and installed that decade-old game on my squeaky clean modern day computer... and I liked it. Imagine that: A game that came out when, what, Windows ME and Windows 2000 were new, installs on Windows 7 totally hassle-free? Wow.
In fact, I liked it so much I am still playing it as time allows, and I am quite amazed at how entertaining playing Deus Ex (the ugly old one) turns out to be, despite its ugliness or technical flaws that were appalling even ten years ago. Deus Ex: Human Revolution, the spliffy new one, sure had me anticipate and expect and wonder, but somehow these games are not just a decade, but really lightyears apart - the atmosphere of the first one just didn't get ported to the new one. Maybe modern ways of making games just don't allow for that special bit, that soul, that spirit to really materialize. The graphics are neat, granted. But it's what is usually bound to happen when people turn, say, Golden Axe or X-COM or Syndicate into yet another FPS experience, no matter how much adventure they tack on to that mostly same old same old action vehicle.
But Deus Ex was already an FPS-style, 3D, "action-RPG" rainbow serving of something awesome, something new... first impressions had it look and feel like crap compared to even significantly older titles, such as Metal Gear Solid or even some of those hand-pixelled Beholder or Dungeon Master titles, all spiced up with the mean big siblings of Robocop's ye olde ED-209. These walking machines of destruction could be disabled by the tricky and sneaky, or blown up by the folks who were happy just to lug heavy explosives around, but make one mistake and they would perforate you into a bloody pulp before you could do something about it.
What Deus Ex did right was this: it was fun to play, it felt fresh and new to be able to test the boundaries of the game, the virtual world. It was a fun sandbox to run and sneak and jump around in, and with more and more augmentations it felt like Neuromancer Super Mario. Yes, physics were frustrating at times, but the story felt amazing, even if I only now, ten years later, take the time to actually read all those newspaper and book text snippets. It is still a royal pain in the rear to drop or throw things to where you actually want them to be, and I forgot about the elves that would remove all my stolen flags and flowers and pots and things from my office once I left through the front door. Still, coming back after ten years makes me respect Deus Ex (the ugly one) even more - I see things, tidbits, mechanics that would later come back even in completely unrelated titles like Fallout 3.
Don't get me wrong, I am not bitter, not really missing much of the old gaming days, except maybe that there was far more room for experimental and new types of games, beyond FPS and tacked-on online-multiplayer. I do hope I will finish Deus Ex: Human Revolution eventually, and I am grateful it made me go back and have another look at the original, which really is a remarkable title and a great game.