Fans of Thief and Thief 2 are in for a treat. In fact, any fan of a "true stealth" game will love this.
That's basically the game in a nutshell. In fact, you can't play it any other way - third person "action" fans aren't going to like this. But patient stealth fans should give this game a try.
I've read lots of forum complaints about the guns not working well, how you can't fight well, etc... I'm not sure what kind of game these people wanted. This is a game where quiet patience pays off. The guns work just fine if you use as intended - one shot to the head from the shadows.
This game reminds me a lot of Thief and Thief 2. In those games, you really couldn't fight much at all - you either stuck to the shadows, or it was over. In fact, this game IS Thief without trick arrows, and with levels that are a bit more linear.
A lot of people have mentioned Splinter Cell as a comparison, too, but it's not a good comparison. This is a very simple game in comparison to Splinter Cell - you'll pick up the controls here in about 30 seconds. Which personally, I like (I never could remember what buttons did what in SC).
VA is very, very minimalist - you don't get to hoard items, you don't get lots of gadgets, you don't have tons of weapons. Just sneak up, press A to kill, drag the body away, rinse, repeat. Some people call that boring - I call it tense, challenging, and fun. The only gadget you get is the morphine shot, which adds just the right amount of "fun action" to the experience. But you only get one at a time (so far, anyway)
I haven't seen much in the way of glitches or the like. Perhaps many glitches show their head if you play a more action style?
Again, this is for stealth fans. If what I wrote above sounds boring, you won't like this game. But if it sounds interesting, check it out.