I am currently in developer beta track, and I must say I am overall somewhat satisfied after going from beta 1 to beta 4.
I don't have a developer account, and I don't want to register for developer program if I don't want to develop software and send it to App Store.
I feel glad that Apple doesn't do UDID check for such devices, giving users like me a chance to throw pre-release software to the wild, witnessing its progress of going better and better. Umm, occasionally I would think I am just looking at a child growing up, although I don't feed that child. (haha...)