As I've mentioned before, I've been poking at a gmail backup application based off libgmail. It's been making slow progress, partly because I've been distracted by other things (such as Project Euler), but it hasn't completely stalled.
Recently, while fiddling with it, though, I hit a snag - libgmail would throw an exception when trying to access certain threads. After much head scratching, and testing, I eventually twigged that the problematic threads all included messages sent via google chat. A little focussed debugging showed that gmail creates pseudo mail messages for these when accessed via the API libgmail uses that don't quite match the messages libgmail expects. A little crude patch later, and the problem was fixed for me.
Thus armed, I submitted a bug to the Debian bug tracker, at around 19:00 local time. At 21:00, I received a acknowledgement from the maintainer, who had forwarded upstream, and at 21:10, I received a note that a patch had been applied upstream. Just over 2 hours from bug report to upstream fix strikes me as pretty good going.