best leveling spec for rogues while questing?

[Newborn]

my rogue isn't seem tobe doing alot of damage and it can take like 30 seconds or something to kill 1 mob. it's currently combat.

 

[Mysigt.]

Sub, I two shot mobs.

 

[Flipper]

my combat rogue leveled just fine until he got to level 80. the difference between wotlk and hyjal is huge for a rogue, he barely even killed one mob without dying the first few quests. after he had full 272ish quest gear it went smoth again with combat

 

[Phog]

Conventional wisdom will say combat to level, but I haven't leveled combat so I couldn't say. My rogue is now almost 81. I went subtlety all the way up - heirloomed to the gills, though. I had no problem. Sub is nice if you intend to PVP along the way.