Actually it didn't, but (2.6.38-0.rc2.git3.2.xendom0.fc15) does at http://koji.fedoraproject.org/koji/taskinfo?taskID=2744376
I also now have a build of xen-4.1.0-rc2 at http://koji.fedoraproject.org/koji/taskinfo?taskID=2744030
I am presently testing these Xen and kernel packages. My initial impression is very positive. I am able to boot into X within Dom0 on my previously difficult hardware. Previous experiences are documented on this list, beginning with [1]. My WiFi adapter also works. So, I agree with Marko's statement so far, "Dom0 is now usable as a desktop computer." I will continue to use this as my primary environment and will report any issues I come across.
Now, the last issue remaining for me is the backend drivers. My understanding is that, in the absence of backends being accepted upstream, we can use QEMU-based drivers. This would be acceptable for our work. Has anyone been using these with Fedora 15?
[1] http://lists.fedoraproject.org/pipermail/xen/2010-March/005014.html