The system I had been using, MediaWiki, is excellent,a nd I haven’t had any problems with it. The only issue is one of resources: I’m trying to cut down on my web expenditure and the wiki used a whole database and a big wodge of filespace. By hosting the wiki elsewhere I don’t have to worry about that anymore.
Also, wikispaces is a really good system, with a nice wysiwyg editor, so I think it’ll be better too for anyone who fancies helping out too. I know a few people registered on the old wiki, so apologies for any inconvenience.