Subtitle editor for OSX?

An open-source, cross-platform solution is Jubler

I didn't try it, but it has a good amount of users on iusethis.

Never tried this, but is is cross-platform: http://www.aegisub.org/

After i read your comments - IMHO you will need:

1. Make .srt subtitles in any tools what you can manage to work (timing)
2. Optionally repair .srt files in any texteditor - skip this if not needed
3. Test the .srt subtitles with VLC or Quicktime/Perian
4. If everything is OK - embed subtitles into video with http://code.google.com/p/subler/

While I've never used this to create raw subtitles, here's the couple of programs I've tried for a similar purpose:

• Subs Factory for creating the subtitles ($7.99). I've actually used it to editing subtitles, but well.

• Subler for embedding them into the mp4. I've used this once or twice about a year ago, and it did what I needed. And it's always good to see such a nice project is still active!