> Twitter doesn't exactly have that luxury. Twitter's luxury is its existing userbase. Same for eBay, Paypal, and other near-monopolies. Twitter's software is

> Twitter doesn't exactly have that luxury. Twitter's luxury is its existing userbase. Same for eBay, Paypal, and other near-monopolies. Twitter's software is absolutely nothing special. You could have 95% of the core functionality in two weeks as a solo project. (Granted, it probably won't scale to 320m users right out of the gate ...) The problem is that nobody's going to go and use your new Twitter-like service that has zero users. So if I built a Twitter clone, I'd probably get, at best, 100 very inactive users, no matter how great the service was.