Yeah, in the blog post Jason added the example of our thank-you cards, but I personally think the actual product design is even more important. Kevin gives some examples in his "Designing Web Apps Users Love" presentation:
Totally agree. Wufoo has so much personality it would take an entire series to write about them and I didn't think it'd be fair to the other websites. =)
Good question - I wonder what the default breakdown of public vs. private shares for FB users are and how SERPs are weighting FB shares vs. tweets/retweets. Does anyone know what percentage of content on FB gets indexed?