So I'm not seeing anybody talking about this, thought I'd post about it since the demo is out now. Digital pre-orders, on both PS4 and Steam, will net you a 15 minute skit with Berseria's characters talking about the Tales series, like the old Viva - Tales of! DVDs that came out in Japan, and the Tales of Festival skits and such. We don't know how it will be delivered, hopefully through PlayStation Video and Steam's on-demand storefront rather than an in-game thing.
http://aselia.wikia.com/wiki/Viva_-_Tales_Of! for posterity.
Also, pre-ordering on PS4 gets you a ufotable theme.
Dr Pepper. It's an intellectual drink, for the chosen ones.