I think the real question is whether or not bitcoin will appeal to the majority of people who are happy with our current financial system. If it doesn't, bitcoin may fade away or end up as a niche currency used for a tiny percentage of global financial transactions.
Even if bitcoin ended up being used in only as 1% of financial transactions, at a global GDP of over 50 trillion, 1 bitcoin would be worth more than 2 million dollars. That's a market niche I can live with.
The impact of Bitcoin will still be much larger than it's actual use. Bittorrent lowers the price of "legal" online music even though "legal" purchases are a larger market share. Tax havens keep the taxes of other countries lower. Sometimes just the credible threat of competition keeps the potential monopolists in line.