If you're going Horde, Undead is where it's at for Rogue. The 20 second immunity to fear with a 1.5 minute cooldown is very nice. The beginning stats don't have very much punch in the long run, since you'll be getting such a boost from items.
As far as builds, it really depends on what you like. Burst damage at the beginning of a fight and slower damage thereafter, or good constant damage. I'm going for burst damage, because it can really catch an alliance member off guard if they're out hunting. I know when I'm hunting I'm not expecting to be ambushed in the back for several hundred damage. The constant damage with a sword or mace build is also probably better for leveling.