Is it Lion for businesses, schools and the like.
Yes, where there are more people thus computers involved needed to access shared data
Is it not for the "common" user?
No it's not for the typical single user in most cases or those not computer savvy, but it is easier for people who need that sort of thing and not computer savvy with server systems.
Lion Server is Adminstrator software "for home offices, businesses, schools, and more". I use it for 130+ classroom Macs on two campuses. Primarily for creating NetRestore images to update the classroom Macs and checked out loaner MacBook Pros each semester break. But it's also used for mail, calendars, file sharing, etc..
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