Were you one of the founders or early adopters who produced a large number when the algorithm was fast, and then sold them off while the hype was making them valuable? If not, then you'll almost certainly lose money on them. Bitcoins aren't necessarily a bad concept, in theory, except that nobody really recognizes them as valuable (making them not valuable, because economics is mostly complicated tautologies), and the mechanism for producing them transformed them into a clear pyramid scheme.
There was no transformation. A significant portion of the total supply of bitcoins (yes, there's a limit! more on that later) was already mined and possessed before bitcoins were "released." As of now somewhere around half of the bitcoins have never changed hands. It was planned from the beginning.
That being said, it's not inflationary and I'm not sure it's a pump and dump. As I mentioned before, there's a limit to the number of bitcoins that can exist (27 billion, I think?) Once a bitcoin is "mined" that's permanent. Bitcoins that get deleted or lost do not rejoin the heap, which means deleting your wallet is like firing gold into the sun. Well, not really, since gold has value, but you get what I'm saying.
What this all means is that bitcoin is actually extremely
deflationary. There's two paths you can take on it, and I have a feeling the people owning that untouched supply are taking the non-speculative path. You can buy coins low and sell high, but you'd get better odds at a slot machine and either way you'd be paying the mafia (one of the big consumers of bitcoins is the Russian mafia who uses it for money laundering, which helps keep it super-unstable) so you may as well head to the casino.
Alternatively, you can be the inventor or one of the first people to sign on, get a few million bitcoins and wait for bitcoin to become a prominent currency as it
obviously will be (heh heh heh). Then once it's all mined out and deflation sets in and an acre of land costs .00002BC, you bust out your millions and carve out your own Randroid Empire among the ruins of civilization.