UPDATES:
I forgot to say,
Fring is now available for the E90. I'm
not gonna try it -- I don't particularly need mobile VOIP, and I have a very good IM client to take care of IM duty. Fring almost bricked my N70, so I've never had a very good opinion of it. But most of the other guys in the symbian forums are going gaga over the factthat it is now available for the E90.
CorePlayer is now selling (!) their beta version for Symbian S60, V3.x for $25. Yep, they are
selling a
beta version. It works reasonably well according to user reports as long as you don't want it to play movies in full-screen. According to them, if you ask it to "fit-to-width" a movie on the internal screen, it starts stuttering all over the place.