The title of this post is just to went out my frustration at the animatedly friendly line you see in invitation emails for Shelfari (Do we like the same books?) . Actually, I am not frustrated at the service or the way it introduces itself - my objection is to something else ... read on if you are interested. The service is really an amazing concept - I wish I would have thought it and launched it. The way it introduces itself too is really good. Having tackled with the problem of 'introducing' websites myself - I do feel this is one of the better ways to do it. But isn't there is a limit to how many times you invite a user?? My first point is that if a user has invited me to the site and I haven't responded means that I am not interested in the service for one reason or the other. It could be pure disinterest or may be that I don't have time for it. Either way - I AM NOT INTERESTED!! Then why should the website send me a 'reminder' for the invitation?? Th