|Image via CrunchBase|
Twitter need not be a mainstream product used by half of humanity to do really well as a business. Instead of trying to imitate Facebook (O, we also show you pictures in your stream!) Twitter could just deepen the relationship it has with its users.
If Google can help me search through the web, Twitter should at least be able to help me search through all tweets that rest on Twitter's servers. But it does not do that. That one feature alone would take Twitter into the stratosphere. I might not need a Dropbox. Twitter would be my Dropbox for the most part. Most stuff I like to save come in the form of URLs.
If you were to force me to pick between Facebook and Twitter - and I am glad you don't - I would pick Twitter.
So if you can be so well positioned for both search and social, and you were mobile before mobile became mobile, what gives? Beats me.