Well, if it's been more than 24 hours, it sounds like a problem to me on our end.
You could try this, though: close the software, clear temporary internet files, and re-open the software. This really does sound like a caching problem, but at this point I don't know if it's your local cache (i.e. on your computer) or our caching system.
(If you could try seeing if your friend shows up in the software on another computer, that would help narrow it down.)
I'll look into this, at any rate.
Jessica Zahn, Zune Social Program Manager ~ This posting is provided as-is with no warranties, and confers no rights.