Though I do use nginx and am very happy with it, I am somewhat put off by the fact that I reported a bug five months ago (including a working patch for the problem) and no one seems to have as much as looked at it [1]. (Granted, this is in a module, not in the core server, but in general the community process for the project seems messy and vague.)
Yes, I agree - nginx's community feels a little strange, at least to someone who hasn't tried to really get involved. Apache, by contrast, is a huge, loud, unruly crowd. Whereas the nginx author seems to be one of those quiet, aloof, l337 h4x0r types. Which is consistent with software that is a) really fast and b) not responsive to change requests. :)
[1]: http://trac.nginx.org/nginx/ticket/242