re only affecting emulators: see @pmuellr's reply below - the bug in question affects 2.2 devices also. Since we're a community-driven open source project, you can see the discussion process :)
http://groups.google.com/group/phonegap-dev/browse_thread/th...
Again, "such significant performance gains for our users" is just FUD when you're talking about arbitrary benchmarks. An app built using Forge and PhoneGap, providing the same functionality, with the same UI layer, would be a much better measure of that. I'd be happy to be proven wrong.