Twitter's challenge will be matching their own financial needs with those of the large 3rd party ecosystem that has grown up around them. It is 3rd party innovation that has grown Twitter, not Twitter's own brilliance.
If they alienate those who share the ecosystem (and their users) they will have a problem. If they only wait for third parties to innovate, they will also have a problem. Good luck to them on this job - sometimes stating the issue clearly is the biggest part of finding a solution.