"I know this is hard to believe, but Facebook really is a commodity product, and Friendster and Myspace have been doing it since years ago, and Diaspora is going to do the same thing, except be private and secure" - said someone everytime FB added a controversial feature.
There's definitely buy-in and momentum of established products...but sometimes, products in the same space can be differentiated in ways not directly related to their core. Github makes it substantially easier to share and collaborate. And that is why many people prefer it. If you reduce it to "Well other places have git, too"...then that's missing the point of why Github appeals to so many.
"Github makes it substantially easier to share and collaborate."
Unless you're using git, in which case, it's exactly the same: unlike facebook, I don't need my best friends to be in my git repo to make it useful.
In any case, I'm sure there are some folks for whom pull requests or browser-based editing (again: not unique to github) make the difference. But for a team of developers who need private repositories, it's six of one, half a dozen of the other.
There's definitely buy-in and momentum of established products...but sometimes, products in the same space can be differentiated in ways not directly related to their core. Github makes it substantially easier to share and collaborate. And that is why many people prefer it. If you reduce it to "Well other places have git, too"...then that's missing the point of why Github appeals to so many.