Maybe worried is a bad word then. I'd say vigilant, or market aware, but worried? By your definition every company should be worried all the time and that's no way to run a company. It's nonsensical to think that.
I think worried is appropriate. Running a company worried or even paranoid when you're the top dog is the only way to stay the top dog. Shareholders don't really care much about how you got there, only their return. Microsoft has made sizeable investments in emerging markets (tablets and phones) and are bottom feeding in both. And their cash cow, Office, is squarely in Google's sights who is continuously wining and dining decision makers. They're worried. Windows desktop OS is really a non-issue here to be quite honest.