I don't think I'm going to jump in on this one, partly because I don't really understand it. It may have a long term future (or maybe another cryptocurrency will prevail), but in the short term I'm sure we're in bubble territory, otherwise we wouldn't have this thread!
I fully expect to see a pretty large and rapid drop in the value of bitcoin in the not too distant future (or maybe I'm hoping for an opportunity to say 'I told you so', as I'm not invested myself). If (when) the price starts to drop, how quickly can you sell bitcoin in exchange for pounds, especially if everyone else is trying to do the same? In the end, what matters is being able to convert your 'profit' into something that you need or want.
It's a pity that it takes this sort of 'fast buck', headline-making 'investment' to make people sit up and take notice, when most of the population keep their savings in a bank or building society account earning one or two percent.