I'm pretty shocked by the generally disparaging remarks regarding bitcoin.
Nearly *all* currencies are speculative to some degee, just think of the exchange market. Investing in euro's doesn't seem like such a great idea at the moment but that certainly wasn't the case before the credit crunch.
As long as the supply is limited (which it is) and there's a demand, bitcoins will have value. Many of you are assuming there is no demand, clearly you haven't visited the silk road.
Bitcoin serves a purpose, it's digital cash, pure and simple. As long as people value *relative* anonimity in digital transactions (and there will always be a section of the population that does), there will be a demand.