Um, I haven't done it, but just by looking at the site it seems to be along the lines of paying to have yourself listed in a "Who's Who" and the like. It doesn't say anything about the star's name being recognized by anyone except the people who see your certificate or who read the book the company sells. If international astronomy organizations recognized the star names, then sure, I'd do it. As it is, it simply looks like it's a pretty certificate and a placeholder in a book full of the names of other people who've bought the pretty certificate.
That said, if you have money to blow or it sounds cool to you, why not? You can always pretend someone else recognizes the fact that it's your star.
