Your website will still be available until 30 June 2012 even if you upgrade to Lion. You do not have to transition to iCloud until then even if you upgrade to Lion but you can - there is a new iCloud System Preference.
I'm using OS X.10.6.8, and before switching to Lion and then to iCloud, I'd like to know what will happen to my web site which is available (i.e hosted) through my iDisk?

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