Skype's Android shackles are broken, 3G calling hacked into reality
engadget.com
engadget.com
I'm hoping Google gets their act together integrating Gizmo with Google Voice, but until they do this is a great stopgap measure. In the long term I'd be much more comfortable relying on open protocols/apps (SIP and Sipdroid) than Skype though; they have been abusive in the past and even pulled their app for a time.
I kind of almost made a call once this way.
http://www.xeudoxus.com/android/Skype.apk Is the link to the unlocked skype app.