Convert YouTube Subviewer to DFXP, SubRip, or QT Text
No guarantees on this one. Double-check your output. It should work with YouTube .sbv files, using most modern browsers.
Instructions: Paste the contents of your downloaded captions.sbv into the left pane, choose desired output caption format, click Convert, and copy the right pane's content into a file for use in your QuickTime, Flash-based, or other appropriate captioning player.