They've given beta access toeveryonea few handfulls within http://steamcommunity.com/groups/familysharing, so if you want to get in, maybe try joining the group
They gave it to everyone in the group. Not just 'handfuls'.Steam Community Group post said:Good news, everybody currently in this group should have access to Steam Family Sharing now. Thanks to your help we fixed a bunch of issue, but please keep on reporting bugs and providing feedback.