OK...my 2 cents on this one... Inodora is the class leader but he is mainly HaT / Combat spec - tho he seems to know a lot about muti too
Jokes aside...you have too much hit, no expertise and low crit...and good haste rating. Keep in mind that hit rating increases the chance to hit the target (i.e. not to miss) but then a second roll is done to determine if the target blocks/parries/dodges the hit. So all hit no expertise is like no hit.
I've seen many rogues in WOTLK ignoring the hit cap (315 is enough) and going for high crit chance. Remember that about 270 hit means all special attacks land. So they reach that and then stack crit and haste and AP.
One other important aspect is gemming - replace any AP gem with agi gems. Agi gives u half the AP but u gain crit so that is a major improvement.
Weapons are another issue. U don't need accuracy on weapons, your best bet would be Mongoose on the fast weapon and Berserk on the slow one...or dual mongoose or dual berserk... or AP enchant... Acuracy is crap for you.
One other thing I would do is remove the points in Improved SnD and put them in Precision so that 315 hit rating is indeed the cap for you.
And...that is about it...
PS: for PvE muti u need fast weapons (Webbed death + Murder) while slow weapons are mainly for PvP due to their burst dmg.