Make the image of Bitcoins better by creating a useful service that needs BTC to function. Right now, Silk Road is the only mainstream application that is created around bitcoins inherent utility. Once there's a popular bitcoin only product, the image will change in a good way.
This. Also, getting people who are enthusiastic about BTC to stop focusing on "da guvurnmint" when explaining BTC. When the average person hears words like "decentralized" and "anonymity" they will pause and wonder what exactly you are doing that needs to be so hidden from the government in the first place. These are all people who use facebook and twitter, so being non-anonymous is a GOOD thing to them.