Inconceivable is currently running on Wordpress 2.7 and loving it. Our reasons for using it were its vast plug-in selection, extensibility, and ease in updating content. (Sadly, only about two people on the team know any HTML/CSS and, unless that changes, the site is stuck in a rut.)
At least this way, we have a site for future years the can update it.
Oh, also it's currently using a theme found online, not a team-created one. Haven't gotten around to doing that yet, though I probably ought to, seeing how kickoff's in eight days.
inconceivable.usfirsthost.com