For those who want the gory details and speak Spanish, there's a discussion
on ultimonivel.net. Wikitle was taken down because of a very generic email from some "copyright agency". Other sites got the same email but chose to ignore it. Wikitle published its source code, so now there are a number of clone sites. The most active ones seem to be
http://subtitulos.es and
http://subswiki.com
And there are rumours about some wikitle people spamming the clone sites because they're envious now. What a kindergarten
The problem with all those wikis is that they're almost only used for Spanish subtitles and for TV series. It's not a limitation of the software, but of the community that is using them. I really like the idea of a subtitles wiki. I wish there were a really international wiki for series and movie subtitles. I already suggested a wiki or versioning system for opensubtitles some time ago, but I know it would be a major undertaking.
(And tvsubtitles.net is back, but it's not a wiki.)