From what I've seen it's got a fair bit of screen tearing and graphical issues on 360 too. Neither version has enough polish nor shows the right balance between on-screen detail and performance IHMO. Still, at least the gameplay has gone beyond tech demo levels so I'm actually expecting to enjoy this more than AC.
Also, the underlying engine has always performed better on 360/PC vs PS3 and despite the huge budget it always seemed unlikely Ubi were going to tinker with it enough on PS3 to gain the additional optimization needed for the game - as with AC (which also had it's fair share of glitches on either console) the developers seem determined to produce a game which slightly outstrips the capability of its tech to support it.
Try to be reasonable... its easier than you think...