How can I integrate it with vBulletin

Ok, I have a wordpress blog and a vBulletin forums. My question is that how can I integrate the vBulletin users into WordPress i.e., if they logon to their vBulletin a/c they get logged in the wordpress to as a user.

Also, I wanted to know how can I embed the wordpress in such a way that every time I make a post, a new thread is created in vBulletin and clicking on the heading takes you to that thread in a specific forum like news and clicking post new thread in that forums (only for admins and mods) directs to the create section in the wordpress blog admin area.