I was just made a Silver member on US today after they matched my similar status on Northwest. I'm taking advantage of a couple of the el cheapo fares from over the weekend.

My question is this... do Silver members get free upgrades (space available of course) on US? If so, is it automatic or do you have to call and request it?

Yes, US Silver Preferred members get free space-available upgrades within the US, Canada and Caribbean. You do have to request the upgrade by clicking on "Apply E-Upgrades" after purchasing your ticket online, or by calling the Silver reservations line.

The upgrade will clear the day before departure, at 12 midnight Central time, if space is available; if not, upgrades clear at the gate based first on status (Chairman's and Golds first) and then on check-in time within your status group. For the best shot at an upgrade if it doesn't clear the day before, use online check-in at usairways.com exactly 24 hours before the departure of your first segment the next day. If you check in 24 hours prior, you're likely to be first on the gate upgrade list among all Silvers on your flight.

I know it depends on each individual flight or route, but how easy are the free upgrades to come by on US? On NW, I'd say my upgrades go through 90 percent of the time or more. Should I expect the same on US?

90% as a Silver is unlikely, unless you're flying at very off-peak times or on routes with few elites.

My upgrade percentage when I was Silver was somewhere in the range of 30-40%.

My SP upgrade luck was in the range of 90% back in 2003. And some fairly tough routes, believe it or not.

-JC