I don't see how frappuccinno is any less descriptive than facebook, it's a portmanteau of frappè + cappuccino. It never crossed my mind it was a Starbucks' trademark until now, I've seen it used everywhere.
For a while I was looking into opening a coffee shop and it's fairly straightforward to license names and sell coffee and coffee products from a lot of major coffee companies. Not that I care for Starbucks coffee, but it was the biggest brand that business brokers pushed on me.