Excuse me for the pun, but someone had too. Dishonored came out on the same day as XCOM and people had their work cut out for them choosing between this and XCOM. I chose Dishonored and later XCOM, but unfortunately I had to sell Dishonored to get the other.
Either way I enjoyed the time I had with Dishonored but...maybe its a little bit overrated? I'm not saying is a bad game, its fantastic, but maybe just not as great as most would have you believe.
The game is a great return of the Thief/Deus Ex formula, without being as good as either of those games. Its great for sure, I had a hell of a great time getting to those executions. There is so much to do, and it is replayable in a way, but not as replayable as everyone is saying.
You can see everything this game has to offer if you do a mixed runthrough, same as Deus Ex: Human Revolution. The combat is fun and varied, but if you do stealth you won't see much of it. It reminds me of Skyrim's combat, but not as floaty and involving. The combat spells can be fun to use, and finding secret areas in the levels are fun, as they can be gigantic.
The executions themselves are...lacking. They are not on par with Hitman: Blood Money, but they service the game. Also the ending to a rather good story blows. Seriously.
While I did spend most of this review criticizing it, this game is fantastically fun, and can show you how much of a bastard you really are. I advise you to buy this game, if only to help fund a follow-up that maybe, can be the true return of Thief and Deus Ex.