As a Physical based damage dealer, Rogues are defined by their weapons, even more so than most classes. Our damage is almost entirely based on auto attacks and weapon abilities while levelling (poisons make up a negligible amount of our damage as
Subtlety), so it is important to keep your weapons up to date - While other gear can help you out, it pales in comparison to how important a strong mainhand weapon is. When looking for a weapon, you should consider the raw DPS of the weapon as well as its speed - slower weapons are far superior for your mainhand, while your offhand prefers a faster weapon with good stats (although your offhands speed matters far less than your mainhands speed).
Once you have picked up the Hack and Slash talent, certain weapon types gain a significant advantage; Maces lose value, while swords and Axes gain value, especially in the offhand.
Some Weapon options have been listed below. Note that due to the obfuscation of gear in WoW Forever, this list is currently incomplete, and will be updated as new weapons are found after launch.
Both - Level 10 -
Blade of Cunning
Horde - Level 14 -
Chanting Blade
Horde - Level 18 -
Edward's Knife
Horde - Level 20 -
Wingblade
Both - Level 20 -
Tail Spike
Both - Level 23 -
Meteor Shard
Alliance - Level 24 -
Phytoblade
Both - Level 24 -
Outlaw Sabre
Both - Level 30 -
Torturing Poker
Alliance - Level 30 -
Subdued Dragon's Fang