the light pen tho is kinda interesting, also the int is a kinda huge ES buff (20%+ inc. ES) o:
tl;dr its definatly interesting, would have to see it in an efficient build, its not horrible, but as it currently is with the current builds it will be outclassed by pledge of hands or average rare staves.
The penetration modifier (no innuendo involved ;) ) is mostly what caught my interest since you rarely find an item with that modifier. Hell, I think Nycta's Lantern is the only other item that involves with penetration (but it is a support gem, so it cannot be stacked). I say this item has potential to be good, not incredible.
Honestly, I already have a build that uses Pledge of Hands (for Incinerate), so trying another staff like this one can be refreshing to say at least. I hope it gets really underrated, so I can buy one cheap. :3