For open source I suppose, since GitHub being so popular makes it easier for people to contribute to your project. Still, though, the only obstacles in using Bitbucket for those purposes (that I know of) are that you need to sign up for a Bitbucket account and learn how to make pull requests. As far as resume code goes, I wouldn't trust an employer who thinks having code samples hosted on Bitbucket is a mark against you. There's just nothing different between GitHub and Bitbucket in that case. Or is there some other issue I'm not aware of?