UPDATE 12/11/10: As John noted in the comments below the most recent beta can be found at the WPBook download page at WordPress. Get the latest copy of 2.0.10 here: http://wordpress.org/extend/plugins/wpbook/download/
Today I am uploading a new beta version of WPBook. This version needs some testing before being forked into core so if you download it and have any problems let me know.
You can download the version here
New in this Features version:
Facebook Avatars – if you have the gravtar setting on and the visiter leaves a comment from Facebook (or leaves their Facebook profile url in the url field) you’ll see their Facebook Profile picture instead of their default gravtar. This is true for both your parent blog (outside of Facebook) and the app view (inside of Facebook)
New Admin Layout – The WP-Dashboard admin page has been completely redesigned and organized into three categories: required, Streaming and Facebook App View. The “advanced settings” have been removed and integrated into the appropriate place in the settings. Tooltips have also been removed. Hopefully this layout is easier to use. Thanks to Ozh’s YOURLS: WordPress to Twitter for the inspiration and some of the code that powers the admin interface and the Tango Project for the expand/collapse icons.
Bug Fixes:
The default of “post to facebook” is now set to true
The link in set_permissons=true now links to WPbook.net instead of the old instructions folder in your install.
Other Notes:
Folder Cleanup, the client and cron file includes have been moved to there own “include” folder
The Facebook Tab view has been moved to it’s own folder inside the wpbook/theme folder
Please let me know any feedback you may have on this build
<Brooke> <Codes> 
Cleaned up a bit (duplicate functions in publish_to_facebook.php) and checked into SVN. Haven’t moved the “stable” tag to 2.0.10 yet as I want to test a bit.