My wife reminded me about this: tonight is the First Friday Gallery/Art Walk downtown. The first friday of every month (excluding January, I believe) downtown galleries and businesses stay open late, with food and wine and music in some places. It’s an art showcase, running from 5 until 9PM. You’re sure to see someone you know.
Somewhat related, BendNights.com has a decent downtown walking map, though it only shows locations for restaurants, ATMs, and parking—there’s no art galleries (or other shops) listed. (That would be a good project for the near future… a downtown walking map with multiple layers for this kind of thing…)