I've seen the premiere of High School Musical 2 and thought that it was pretty good. Personally, I liked the first one, but there are also some parts in the second that I wouldn't mind seeing again like the musical numbers of "You Are The Music In Me," "Gotta Go My Own Way," and "Bet On It."
I wouldn't say anymore in case I spoil it to those who haven't seen it yet, but for those who had seen it: what did or didn't you like about it?