From the publisher's web site:
This month, Unearthed Arcana returns to the mystic character class and the rules for psionics. Based on the playtest feedback you sent us, there are a number of changes you can expect:
The class now goes to 10th level. The core concepts had enough support that we feel confident moving forward with them.
Psionics is more flexible. You have a psychic focus, which allows you to pick one discipline and gain a constant, special benefit from it. Otherwise, you can expend points to use any discipline you know.
Psionics now includes psionic talents, the equivalent of a spellcaster’s cantrips.
Psionic disciplines are now available to all mystics, regardless of mystic order. However, your order grants you a benefit for using its associated disciplines.