http://www.macrumors.com/2011/08/29/mac-os-x-snow-leopard-10-6-9-to-bring-icloud-support/
This is probably just the syncing tool, not the online storage part of iCloud. Or maybe both. Who knows with Apple.
Apple appears to be preparing a 10.6.9 update to Mac OS X Snow Leopard in order to provide compatibility with the company's upcoming iCloud service. The following notice appeared in one developer's .Mac preference pane in Tiger after he had upgraded his MobileMe account to iCloud.
Apple has already confirmed that syncing of Mac Dashboard widgets, keychains, Dock items, and System Preferences are not making the transition from MobileMe to iCloud for any users, but if the alert notice being delivered to iCloud users on Mac OS X Tiger is correct, it seems that at least minimal iCloud functionality may be coming to Mac OS X Snow Leopard in the form of a full maintenance release.
This is probably just the syncing tool, not the online storage part of iCloud. Or maybe both. Who knows with Apple.