I'm from Eugene, and don't think I could handle the weather there again, let alone further north, although if other people reading this are curious, I'd have to put a word in for Portland, if the climate isn't a problem for you.
"Calagator, the community project designed to give Portland one tech calendar to rule them all, has quickly begun to show signs of progress. In fact, events have begun populating the calendar already."
http://calagator.org/
I didn't know Oregon (Corvallis) had such a vibrant technology culture/market.
I don't know that Corvallis is big enough to be really "happening", although it's a pleasant enough place. Portland is a better bet if you can stand the climate. Unfortunately, I really can't. The endless gray just wears me down mentally. I need regular time outdoors and sunshine. For others though, I'd heartily recommend Portland.
Corvallis has Hewlett-Packard. And a couple smaller companies. I'm not sure if it could be called vibrant...I lived there, but I'm always rather out of it.