I once read here on the forums that having a stat over 255 is more or less wasted as once an attribute reaches 100% as it doesn't increase past it. Eg: having intelligence at 500 would be 2x as quick as having it at 250.
My Raiding attributes are:
Intelligence: 254
Discipline: 237
Strength: 0
I think having a stat of 260-270 is about 100%
I know a lot of people shard duplicate armour, but it may be worth thinking if its better suited for your play style then your current gear.
I don't really use melee that much, so I have managed to mix and match raid gear till I managed to get the above.
My current mission is to try and incorporate gear so I can have sunbreaker's on with out messing up my stats too much.
Then again, it may be a moot point to do so now as the expansion is around the corner!
What's your attributes and why?