I write ruby (though I haven't done much rails yet), and went to literally dozens of SFRuby meetups. Yes, recruiters did swarm in a few times. However, it was a massive waste of time, hopes and energy since every single one of them was looking for a senior engineer. Interestingly, the last SFRuby meetup I went to at Carbon5, where we all had to introduce ourselves and what we did, about 5-7 of the twenty some people there were unemployed.

I've actually had better success finding work through HN and through friends of people I've worked for before (once again no help to someone just starting out).