Well to be honest, 100% swings in a day are TERRIBLE for a means of exchange. Price stability is very important for exchange. If you can't even worry about buying or selling because you are worried that your bitcoins will change in value in a day or week it is bad news. I dont think bitcoins primary function is a store of value, so that doesn't bother me. I would much rather have them stable and at $5 then swinging between $50 and $100 all the time.
I agree with this. The problem is, if the price is $5 then the economy is non existent.
As much as I love the idea of bitcoin, I feel that it have to face very strong established forces which will always drive the price down.
Let's say we have a p2p exchange - or a better exchange without mtgox problems, there would be massive campaigns against BTC driving it's price down no matter what.