It just occurred to me, but doesn't the new MoP talent system "fix" the problem for 10m raiders needing an OS but wanting/needing a pvp spec too?
Not sure if there will be a mat/cost associated with changing talents but as long as that's not too prohibitive, you could use switch to raid talents when you zone in and back to pvp talents before zoning out.
Assuming that's correct, is there a chance this helps balance world pvp?

