Saw this over on NeoGaf:

Someone posted this preview from Mirror on reddit. It covers the first couple chapters of the game.

In single player, I managed to battle my way through the first couple of chapters and, my word, this Crytek game is bloody gruesome… and bloody brilliant.

Combat:

It is a pretty simple combat mode - sword attack (x), shield bash , evade (b) and block (a). But do not fear... this NOT a button-mashing game. The timing of your combat leads to a flurry of activity which needs careful thought - but results in glorious gore and slashing satisfaction (think Batman Arkham series with a generous sprinkle of Assassin’s Creed).

Combos:

Combos are a key ingredient while fighting and timing your strikes (button colour coordinated taps) leads to more XP and more blood. The pre-animated executions are fantastic and varied enough to make you whoop with joy as you watch an arm go flying.

Another nice touch is the Focus mode which slows down attacks while speeding up your combos. One slightly annoying thing about the executions is that if you get the colour-combo wrong (i.e. hit X instead of Y) you only lose XP, as opposed to your attack being broken up and you having to go again at the bad guy. Only a minor gripe though.

Visuals:

Visually, an Xbox game has never looked so bloody good - or bloody. The battle environments consume you, the fires repel you and the grandeur of Rome envelopes you. Armour glistens in battle, smoke thickens and the blood shimmers as it slides down the glinting swords of Roman centurions.

All this without interruption or frame rates struggling to keep up with madness of war. No lagging, no delayed lip-syncing. Everything is seamless and every soldier is an individual - which looks remarkable when you put hundreds of them together on the battlefield.

All of which makes for a spine-tingling experience which leaves you wanting (much) more.

The best action/adventure games today are at least ten to twelve hours.

ah the console war!!! will be bloody this gen

The game hasn't been finished by the aticles writing.  If it is 5-6 hours, maybe the style of the game lends itself to to it's short length. 

Neither of us have had a chance to play it and come to any conclusion.  I think we both know that the length or price of the game have no impact on the quality of the game or whether we find it to be any good.

I can't disagree that if the game is extremely short, the replayability better be outstanding.

Well let's not forget about MP.... If fun that could also give it way more game time

If you're opening this up to six hours, then this is beyond easy.

Off the top of my head, Super Metroid, Metroid: Zero Mission, Devil May Cry 3, Star Fox 64, Metal Gear Rising: Revengeance, and Pikmin can all have their "campaigns," for lack of a better term, beaten in less than six hours easily without any need for speed running techniques. And some of these games aren't even from that long ago. MGR came out this year.