Don't upgrade to Lion and don't get involved in iCloud. It's a mess.
I have been following the iCloud introduction with dismay and I agree completely. Because of previous experiences I usually wait a week or two to see how things are going before I make major software jumps.
Unlike previous system and application upgrades, which can be reversed via backups and clones, iCloud appears to be unchangeable. At present I think I will wait at least 6 months or more for an acceptable solution. Supposedly I can use Mobile Me till June 2012 and then I may have to switch eMail service.
Lack of resolution will guarantee iCloud a cloudy future