I mean, flex builder for windoze and macos was made by programmers. If they cannto program the same thing for linus, then I cannot see a justification for them calling themselves programmers.

This really is a simple process of code-porting - and adobe will know how to that as well as anyone else.
I am a programmer myself, I understand the processes involved. they are just leaving this on a backburner because they simply don’t want to

I’ve not really noticed any issues with the Alphas, but then I’ve only done very light work with FB, so it’d also be interesting to hear what’s holding it back, is there an issue list anywhere?

From what I heard, the design view code for Flex Builder comes from the Flash Authoring design view, and this code is heavily rooted to either Windows APIs or Mac OSX APIs. To bring it to Linux would be a heavy undertaking. Eclipse was already very cross-platform. Flash and other Creative Suite products are not. It may happen eventually, but unless there’s heavy demand, I predict that Adobe will probably keep it on the back burner.