Frank @ Mefeedia mentions an interesting tactic, and one I've been a proponent of for awhile: a "Meet the Videoblogger"-esque behind-the-scenes culture that promotes the culture of videobloggers.
I'd actually like to see the idea taken a bit further toward a "star support" culture -- Veoh's Viral is a good comparison here. In a perfect world, think "The Tonight Show" (or the late night show of your choice), in which content creators are invited on as guests, with a central host and a few roving reporters. Kind of like a "real" version of The Clip Show, with the "real" Jim Kirks as the host... or me... ;) Is that something Mefeedia can make happen? Oh, and yes, creating great content is always the key to retaining a healthy audience.