Typically they are only enforceable if you leave, or sign some sort of severance package, if it can be enforced at all.
It's very doubtful it can be enforced if you're fired.
Which noncompetes have been repeatedly held unenforceable (acquisition NC's not included, but they usually have a short lifespan) in California?
He lives in Washington legally. Non-competes are generally enforceable even in California in the case of acquisitions like this. It's hard to argue that he wasn't given sufficient "consideration" which is usually the main issue for normal non-competes in employment contracts. IANAL though.
I doubt it could stop him starting a personal blog or tumblr. he might do it just to find out what happens