It's funny because a few weeks ago, people were saying that $20 was a bubble. The difference between now and the June 2011 bubble is that the bitcoin economy is much bigger. There's a lot more trade and a lot more people with stakes in the game. Legit sites like Wordpress.com and Reddit are accepting BTC and that will continue to expand. Also, MtGox is partnering with Coinlab to make bitcoin purchases much easier for US citizens, who are the biggest demographic. Unless something catastrophic happens, like governments banning bitcoin exchanges, I don't see it going below $20 ever again.