Well, it finally happened... only took a year and I got some first class upgrades.

Was #1 on the upgrade list last Monday morning from BWI to DEN. When I got to the airport they gave me that AND got me upgraded for my connection from DEN to BOI as well.

Then on Friday flying back from BOI I got an instant upgrade at check in on my first leg to SFO... sadly due to delays that was scratched as I got on a different plane.

I still don't think Silver is necessarily worth stretching for, but if you're not flying out of a major UA hub it seems like the upgrades are much more possible.