Well, people are still buying things with it. In fact, in the longrun I think you could probably argue that it is undervalued. The more and more merchants start accepting it the more valuable it will become. All it'll take is one big company to start accepting it and boom. Gradual or quick mainstream acceptance will push the price up vastly. Let's see what the price of 1BTC is and what it can get you in a years time. Only time will tell on this one. I'm looking forward to the ride.
No, it is not
undervalued if the merchants don't accept it
right now. Such mode of "reasoning" is called wishful thinking - "an attitude or belief that something you want to happen will happen though it may not happen or unlikely to happen at all". With such volatility I doubt strongly it will occur any time soon if ever ("one big company to start accepting it and boom")...
But merchants do accept it. Such mode of "reasoning" is more optimism than wishful thinking. As I said, only time will tell and I'm enjoying the ride.