Base Site User roles with multisite

Hello, so I have WordPress 3.1.3 installed on a Linux server. I have multisite enabled ( both User accounts and sites can be registered). It used to be that in the super admin section ( before the whole Network admin, and site admin switch.) that you could select the role users are given when they sign up for your site. So say bob registers on ex1.com , and during registrations, he makes his own blog at ex1.com/bob . How can i set the role that bob has on ex1.com ( the “” base “” site) Thanks!