I would argue that SF was always pretty shitty, because it focused entirely on advertising. I remember Chris giving a talk comparing the signup process of GitHub and SourceForge. SF had like 8 fields and GitHub had 2. This was because SF wanted to know ad demographic info - where did you hear about us, etc. GitHub just wanted a name and a password. But this was the difference in everything - SF cared about advertisers, not developers. GitHub never thought about what anyone other than the developers using the product wanted.