Well, so what? Simon Marlow, Haskell's lead compiler developer in recent years, quit, leaving arguably a much larger gap than @paulp leaving Tyepsafe since SPJ is wrapped up in leading some English education initiative.

Anyway, shit happens, gaps are filled. Languages, once established, are larger than any one developer, no matter how brilliant the individual may be.

It's worth noting that @paulp is as active as ever in Scala, working on his new collections library and contributing to Scala now from the outside -- he may have left Typesafe but has not in anyway left Scala. As he says, he has a "sickness" for language perfection, and fortunately for we Scala users, Scala is the target of his illness ;-)