I really, truly do not understand Twitter's thinking. I'm sure on someone's spreadsheet of imaginary numbers it looks more attractive to be a billboard, but Twitter had the opportunity to be a true platform. A platform gives you control. It's a longer-term play, but my goodness the opportunities missed. Including this one, which could have been in play years ago.
Whether people will actually use this feature is a whole other question.
[1] http://www.crunchbase.com/organization/sell-simply
Edit: Clarify first P.