Re: Huge Security Hole with wp-admin?
If you are sure you installed Buddypress correctly, you need either some sleep or maybe some coffee.
This is not some bug in Buddypress. Are you sure you didnt register a blog with the account, and that the backend you see belongs to this blog? It is quite clear that members are administrators on their own blog. Can you see the Buddypressmenu in your menu to the left after logging in?