Do most companies of any typical size really need distributed source control?
Git works well for open source projects where people from all over the world are collaborating on a project at vastly different times, where the validity of check-ins is determined by merit and a web of trust.
At a company where, say, a commit requires QA analysis or a configuration manager's approval and/or documentation, or to reconcile a revision number with that in a bug report, I would submit that distributed control such as Git really does not make sense, in the sense that the paradigm shift is not warranted; that it does not yet fit well with existing CM processes (a social problem); that it does not integrate well with existing tools, third-party and otherwise; and that it has poor Windows support.
Not that it's not good; it's that I am quite skeptical to believe that it's the right tool for most corporate environments. I look forward to some of the other responses for insight.
