sd said it best when he basically said, "Invest in what you know, like, and are happy with." That also holds true in the investment advice department...take the advice that addresses your style of investing, try to learn a little bit from somebody who invests differently than you do.
Outside of retirement investing, I still invest long term and do not worry about making a buck or two quick. I also invest in companies that have a solid history of paying dividends.
At some point, I'd like to better understand investing in currency. I think that would be interesting because it would likely keep you very up to date on foreign issues- both political and social.