Hi I' m a developer and I need to use Lion to test my application. I don' t want to install Lion in a dedicated partition. I need to have only one SO installed n my computer so I wan' t to install the DP4 in my main partition (upgrading snow leopard). Before doing so, however, let me ask you some questions: 1) Can I upgrade my DP4 to the final version of Lion when it is released in July? 2) I checked and all the applications that I need seems to work in Lion. There' s some big bug that make the system unusable? 3) Can I install it simply upgrading Snow Leopard or I need to do a new installation? Thanks a lot!