The advice that everyone gives, which I am inclined to agree with, is that nearly full combat is the best way to go for a levelling rogue. You're high enough that you could do it with assassination if you really wanted to, but I think it's commonly accepted that it's still slower, and only for people who are sick of levelling from 1-60 in combat.
So, you get two swords, one slow one with high upper end damage for your main hand, and spec something like this:
http://www.wowhead.com/?talent=fMZMxAz0bxqru0got
That's not authoritative, but its good enough for just levelling. Use the last 7 points for whatever you want, maybe endurance or relentless strikes or malice or improved evis. Or spend them in sub and get dirty tricks and/or camo (they're not ++dps but I personally find them really fun since you get much more flexibility in darting in and out of the shadows) Don't get too hung up on what is going to make you do all the damage in the world, you'll have more fun if you take what feels most fun.
Well knows he who uses to consider, that our faith and knowledge thrives by exercise, as well as our limbs and complexion. Truth is compared in Scripture to a streaming fountain; if her waters flow not in a perpetual progression, they sicken into a muddy pool of conformity and tradition. A man may be a heretic in the truth; and if he believe things only because his pastor says so, or the Assembly so determines, without knowing other reason, though his belief be true, yet the very truth he holds becomes his heresy.
