I was just going to mention it. I think it's way better than the facebook library mentioned in the article. I'm using for my upcoming app and it was a snap to use it for facebook and twitter
I played with ShareKit for a while and it does include an impressive range of sharing options (and really helped me understand how OAuth works). However I found that the sharing functionality seemed to be tied to a specific visual presentation, which I didn't like. In the end, I decided not to use it because it didn't match the look and feel I wanted for my app.
