Opera has quietly released beta 2 of the Opera for Pocket PC browser that supports both WM 2003 and WM 5.0. The new version adds tabbed browsing, support for http uploading and keyboard shortcuts. A great addition is the ability to scroll down one page at a time via the space key on the keyboard. There are still some issues for Opera to resolve: fullscreen display, stealing focus from other windows, and download problems with WM 2003.
I have been using Opera for a day now and it is much better than the first beta and is very fast on the Treo 700w. I wish it would import my favorites from PIE, though. This is shaping up to be THE browser for Windows Mobile devices.
(thanks to MobileTechRoundup listener JNGold for the tip!)