This is a rogue's off-hand dagger, probably the best blue one in the game.
Rogues want fast attack speed on off hand for poisons. As of 1.12, the only blue I know of that is faster than this is julie's, which has lower dps.
On an off-hand dagger, all procs occur half as often, so static bonuses are basically always better.
Attack Power is the best stat for a rogue, if you work out the math AP is the single largest contributor to a rogue's damage. Only +20 agility could compete with this, which does not occur on any blue dagger.
AP is easier for other classes to acquire. Warriors get 2 AP per strength. Hunters get 2 ranged AP per agility. It is certainly a nice dagger for both of them though, and could easily be an upgrade.
However, it IS best for a dagger rogue, and also it is THE best off-hand that a rogue could acquire before they go epic (and better than many epics). I am pretty easy going and wouldn't be offended if a warr or hunter rolled against me for this, but I do show restraint on items that are better for them, and I appreciate when it's reciprocated.
