Technically, this isn't a review.
The game doesn't come out until the 25th, so until then here's a promise that I will soon have an opinion. I'm a fan of games like Dishonored and Far Cry 3, where you have the option of using stealth rather than flat-out aggression - it leads to longer, more immersive gameplay and means you don't have to worry constantly about keeping an eye on your health.
Thief is open for pre-order and pre-load, for 10% off on Steam and (hooray!) an extra 25% off that price on Green Man Gaming, bring the price down to about $33 (GMG gives you a key that you add to your Steam library).
I'll post an actual review as soon as I've played enough of the game to feel I've formed a reliable opinion.
Green Man Gaming: http://www.greenmangaming.com/?gmgr=cowavewo
*NOTE* This is a referral link - if you use it, we both get $2.00 added to our accounts.