I've definitely noticed more people I follow on Steemit posting D.Tube videos. And I've seen a few great examples of YouTubers with big followings crossing over to D.Tube. In addition to the potential for increased earnings ($$$), I think the opportunity for reduced censorship is a key factor for the migration. On YouTube, there is much more of the "thought police" to censor your actions & words -- they want to make it as advertiser-friendly as possible. But on D.Tube, there is no real censorship (although I suppose there are other ways to silence voices, such as by downvoting, flagging or blacklisting).