Anyway, since I didn't get a cancellation email, I thought I should spread the word.

When I signed up for the Silicon Valley meetup, I got a single email that read (in part):

Welcome! The next Perl MEETUP near San Jose, CA 
is Thursday, September 19 @ 7:00PM. We will keep you updated via email
+.
[download]

And where there email updates? No. And on reading blakem's post, I go back to the meetup sign and find out that it thinks I haven't RSVP'd? When did it ever ask me to RSVP?

I rather think this meetup concept has some gaps in the current implementation. There's little excuse for dropping the ball after leading people to believe that there would be email updates.