According to Sony, every PS4 will come with a voucher that gives every user 30 days of PS Plus, 30 days of Music Unlimited, and 10 dollars to use on the PlayStation Store. This offer is currently only for the US and Canada.
Music Unlimited is good as Sony noted the PS4 can’t read from external drives, can’t read .MP3 files, and can’t read Music CD’s. So while we wait for a patch to allow access to all of this, we can still utilize Music Unlimited for the time being.
PS Plus opens all the gates for Plus users, including the first free game for PS4. To top it off, the ten dollar voucher has no limits on it. It can be used to extend Plus, buy a new game, or purchase a launch title. This means current owners of launch titles on PS3 could possibly get them entirely free on PS4. That is since games like Battlefield 4, Assassins Creed, and Call of Duty: Ghosts have a 10 dollar promotion going on.