It's 2012, which means that, for most rap artists, there's no more passing around your demo tape with a phone number penciled on the side. No matter what level of success your song attains, the video is a necessity. Any attempt to pretend otherwise is just plain dumb.
Getting our music via the Internet means we experience everything visually as much as we do aurally. Swag matters. You think Kreayshawn would have a record deal without her video? "Gucci Gucci" was a catchy song, but it was the entire lifestyle conveyed through a four-minute clip that really made her career take off.
The same holds true for A$AP Rocky, Chief Keef, and Trinidad James. Videos have always been important for breaking artists; they convey a sensibility and identity. They've also never been as affordable as they are now. An army of videographers awaits your call.