Just this morning I found a bug in Flex Builder 3 Beta 2 and checked the bug database. The bug was there and labeled as fixed for the Beta 3 release. This got me wondering when beta 3 would be out, especially since my beta 2 version was about to expire. I didn't have to wonder long because as I was checking my feed from Adobe blogs I saw that it was released on labs this morning. So currently I am downloading and updating the new version for testing.
Unfortunately, Flex Builder for Linux didn't come out with a new alpha release at the same time. I'm thinking it will be soon though, because that version is set to expire in 18 days. Currently hoping for design view.