Online discovery service StumbleUpon has changed the way its users can access the service. The company announced a new partner program Tuesday and also unveiled a new Web-based toolbar that no longer requires users to register or download the specific StumbleUpon Toolbar, a task that may have turned some would-be users away in the past. The changes are part of an effort by StumbleUpon to offer a new user experience, said Michael Buhr, general manager of StumbleUpon.
