So I'm running the GM version of Lion and I installed the latest version of iCloud. As well as this I've also got iOS5 on my iPad. During DP4 I tried to activate an old expired account that I had, but with no success. Being a bit of a stubborn fool the first thing I did once I had the GM installed was to see if I could get this account active. As it turns out you can. My now previously expired account seems to be active and I can now sync calendar events and contacts between all my devices using this account. However, my email account is not active...although emails that I send to the address are no longer returned to me. When setting up the iCloud account in Lion all the boxes get checked but the account does not appear in Mail. Just thought I'd share, if I discover anything else I'll post that too.