I think we still have a ways to go, we need more big companies under our belt to be able to really reach the layperson. I believe Overstock is currently the biggest retailer we have which is really awesome, it's just a bit of a shame that they don't seem to have Bitcoin mentioned anywhere on their front page, it's only when you go to pay that you get the option. People need to be able to see the Bitcoin logo more places online, if the word Bitcoin is always popping up, eventually some will try to learn more about it.
I've seen the PerfectMoney, Webmoney, and other logos about 10,000 times. I've never felt the desire to learn more about them. Why? Because I'm doing fine with the things I'm using now. I won't start using something new unless I get a big discount. It might be the same with most people and bitcoin.
As most people on this thread have pointed out, knowing about Bitcoin, has no relation to knowing what Bitcoin is, or why it's useful. I had heard of Bitcoin 2 or 3 years before actually looking up more information on
what it was. As soon as I understood what it was, I was hooked.
As jehst said, people may have seen the word Bitcoin or heard it mentioned, but they don't go looking for information on
what it is.
IMHO, for a large population of people to understand
what it is, there needs to be a specialized nationwide commercial in each country about what is wrong with fiat money, and why Bitcoin solves those problems. Play it enough, and you'd have a
LOT of new interested people.
I also wouldn't neglect the power of word-of-mouth. I've done some street-campaigning for charities like Doctors Without Borders. When this type of solicitation first began, many people had no idea what some of these charities were, even though they're pretty big. Now, I stop people on the street and most of them know what I'm talking about and had even learned about it from another person like me.
It might be difficult to apply that strategy to Bitcoin but I feel like combining media exposure with person to person interaction with informed people would make a big difference.