I am having the same problem - only I don't have a "blank" toolbar - I just don't have one anymore.  I did read on another site that if you customize the bookmark toolbar and look for the little purple book icon that says "bookmarks" and drop it into your empty blank toolbar, you should see your bookmarks again.  I did not try this myself, but I do not have a blank toolbar - I just don't have a bookmark toolbar at all.

Hope this helps.  By the way, I am using 3.0.5 Beta.