http://longhorn.msdn.microsoft.com/lhsdk/core/overviews/road_map.aspx
a "presentation layer" called Avalon that uses XML as the basis? prepare for some nasty confusion :-/
Unfortunately what can you do? We have been aware of this issue, and not quite sure how to manage it. The best we can do is make the Avalon brand be Apache Avalon, and make it clear that the cheap knock-off at Microsoft is in no way endorsed by Apache :/.
It's not like the ASF has really deep pockets, or that the name "Avalon" isn't so unique as to be stepping on trademark. There are so many software applications/frameworks/etc. that incorporate the name "Avalon" that it really needs to be used in some way to scope it.
--
"They that give up essential liberty to obtain a little temporary safety
deserve neither liberty nor safety."
- Benjamin Franklin