Okay, so I haven't updated this in a long time. gcc-4.0.2-r1 seems to be pretty stable for most people. We are going to be pushing out a new revision soon that should fix a few more issues that people have been running into. Hopefully in a few more weeks we'll start getting ready to move it into ~arch since most of the tree seems to support it now. If you are running into any bugs, send me an email or assign a bug to me and I'll look into it.
I also added the gcc-4.1 snapshots back to the tree. If you were curious, I added that die into the ebuild because I got sick of people reporting bugs to us that should be going upstream. If you want to use gcc-4.1, I'm assuming you know what you are doing and can file meaningful bugs upstream. :) There is a thread on the forums going for it already, so you can ask for help there. If you come up with a patch to fix a package, I would of course love to add it to the tree, and it would be great if you sent it upstream as well.