Tracking by user attributes?

Hi,

i just installed piwik 0.5.1 and am pretty impressed so far. What I’m particularly interested in is statistics based on various user attributes, in particular “logged in” vs. “guest”. Is there a way to add such user properties to the tracking function call?

Completely unrelated: in Actions/Pages, why are those links not clickable? This is particularly annoying when the links are shortened and therefore not even copy/paste-able.

TIA.