That is really strange. Try deleting, then downloading 2.0 from WordPress.org. Then that one should update to 2.0.1 from my own private update site hosted at wp-updates.com.
There have already been several hundred downloads of the 2.0.1 update, so it does seem to be working as expected.
To avoid possible delays in getting new versions added to the WP.org repository (about a week delay at the moment), I have a secondary update site so I can release important fixes quickly. I don’t know what that message means, but wp-updates.com is the correct source of the update.
There should be Weaver Xtreme V 2.0.2 available on WP.org in a week or so.