It seems like a StackOverflow question because of Trac and SVN (clearly programming tools), but I suppose you could make the case for SuperUser (for Wordpress) or ServerFault (server configuration).
I know some people may not agree with me, but sometimes, since it's a
grey area like Cletus said (and I agree with it), it's better to post in SO, because:
- these are tools that developers are familiar with in daily programming. Programmers are Super Users, but Supers Users don't have to be programmers, so I exclude Super User here;
- "Play nice" is about user experience, and people who use these tools are programmers (This may be a little controversial, since sysadmins could show some concrete user experiences, but I usually more in personal experience opinions);
- you have much more visibility and more chances to have a good answered question in SO since your question isn't too much off-topic;
- you can let the community and experienced people decide if it's programming related (SO has more users with higher reputation and they can decide if your question isn't so programming related).
The 3rd motive is what I think really drives people to decide which website to post questions.
It's a grey area.
Questions can potentially belong on any of the three sites and the line can be blurry. Configuring MySQL might well be considered a serverfault question but then again it can relate to programming issues as well. You'll find questions on SO about PHP session config and similar for this reason.
This is the problem when you try and create demarcation on related subject areas by site. Not that I'm saying we shouldn't do that. We just need to accept there are grey areas.
- Trac: probably not SO as it's not really programming related. SU/SF depending on if its a usage or admin issue;
- Subversion: SO;
- Wordpress: potentially anywhere. You'll find Wordpress questions on SO. If it's about installation or admin, probably SF. Writing code for it then definitely SO.
But that's just my opinion. Just use your best judgement.