First, it is my understanding that the upgrade DVD is the same as the full retail. Same disc. Mind you, I am getting this info. from reading other sites. Secondly, can't say I am overly happy after just installing Snow Leopard. Many programs no longer work and I have to sit here until manufacturers play catch-up. Among those not working... * Letterbox for Mail * Mail Tags for Mail * MiniMail (which looks like it will never be updated and I love it) * Windowshade X (my favorite utility ever) * Tivo Transfer I will say my system feels somewhat more spunky than before but nothing major to say here for the moment other than I like the new Quicktime player for my WMV and AVI files.