I had to do the following to get my site to work with the new 1.00.02 beta AD provider:
I see that with this version, the usernames are no longer in the format: MYDOMAIN\username, but rather just username. To update the existing accounts in the DNN database, I believe you need to update 3 columns in two tables (it worked for me):
UPDATE dbo.Users
SET Username = REPLACE(Username, 'MYDOMAIN\', '')
WHERE Username LIKE '%MYDOMAIN\%'
UPDATE dbo.aspnet_Users
SET UserName = REPLACE(UserName, 'MYDOMAIN\', '')
WHERE UserName LIKE '%MYDOMAIN\%'
UPDATE dbo.aspnet_Users
SET LoweredUserName = REPLACE(LoweredUserName, 'MYDOMAIN\', '')
WHERE LoweredUserName LIKE '%MYDOMAIN\%'
So far so good with 1.02 and these table updates. Kel