I just called Alltel and asked about the WM 6.1 upgrade and they told me it was supposed to be out on Monday, but was delayed. He thinks it was delayed as they didn't get their training on 6.1 until this week. I also checked HTC's site and the old upgrade that enables REV A is gone...
I would expect this to be out very soon.
EDIT:
Just Thought I would add the link.
http://www.htc.com/us/supportdownloa..._id=64&cat=all
EDIT:
Found another site to look for updates of Alltel phones:
http://software.alltel.com