As far as I know govmnt funny money still buys you to eat, while others don't.
I can get
pizzas,
coffee and tea,
baklava,
beef,
Belgian beer (and other specialties),
wine, and tons of other
foods and
drinks. All with Bitcoin. And now with Gyft accepting Bitcoin, you can pay at 50,000+ retail stores as well.
So, as far as Bitcoin is concerned: if it looks like money, swims like money, and quacks like money, then probably...