If I remember correctly, the 8 GB iPod touch is not actually a 3rd generation machine. Only the 32 GB and 64 GB models are. The 8 GB model being sold now is from the 2G line and marketed as an entry-level unit. So if you install iOS 4, you won't get multitasking and other features that will work only on the 3rd generation machines. The only enhancement you will get will be folders if you buy the 8 GB model. It would be better to get the 32 GB model at the very least if you want to enjoy the new iOS 4 features.
But September is just around the corner and it would be exciting to see what comes out....
http://answers.yahoo.com/question/in...0194410AAuAPM5