Ok, I've decided.
I'm going to continue WinAVR.
I would like to come out with a release say in the next 3 months (or less, if I can swing it).
It will contain a new avr-libc release. This will tentatively be 1.8.0. Joerg and I are currently working on bug fixes and patches to avr-libc.
Joerg has mentioned a new avrdude and avarice release as well, but realize that his time is spread thin across multiple projects.
We have to work out what version of avr-gcc to include and what kinds of patches it needs to contain. There's a number of bug fixes that need to be done.
I'm sure there will updates on other tools as well.
Bug reports, patches, and constructive feedback welcome. And help on any of the projects is always welcome too.