We could say that many had an educated guess that Bitcoin would be the way of the future. It's initial promise was brilliant, however at the time of writing it seems to have lost much of its use (e.g. cheap micro-transactions between peers), due to technical and economic issues (limited transaction rates, insane volatility). It's not clear whether any of these will change, so I wonder what people are investing in? I believe what the parent poster was referring to is that much of the investment seems to be purely driven by speculation on the value, rather than its promise as a platform.