Oddly enough, and despite the $200/$400 figures I've seen quoted, the only VDB amounts I've seen in reality at PDX have been $300. Twice on flights to the Bay Area, and once to Redmond (unfortunately, not the flight I was on!)

Also, regarding being placed on UA... Horizon recently put me on Skywest (United Express) from Redmond to Portland for a cancelled flight - about the most seamless transfer ever (and no trouble getting my miles to post, either!)

Dave