Digital Music news says music-industry execs tried to answer the deep question “What will be the next killer app to hit the music space?” at a panel Wednesday in Los Angeles. The best they could come up with: well, uh, ringtones are pretty sweet, so people will probably want to buy music videos for their mobile phones, too.

It’s doubtful there’s much thought behind this apart from “following Asia” as a business model. There doesn’t seem to be the understanding from the labels that ringtones are more about showing off (or self-expression, if you’re so inclined) then they are about enjoying music. Conversely, a video’s about entertainment, so there’s two different paradigms there. The popularity of buying ringtones isn’t a manifestation of peoples’ desire to listen to music on their handsets — and shouldn’t justify high expectations of any other kind of tangentially related content. Perhaps to the labels, everything’s just content waiting to be shoved down a pipe.