Ask a 5e playtester who doesn't give half a fuck about NDAs anything.
Preliminary - It is quite, quite obviously an early "build", and without a PHB or somesuch to look at, all we playesters know is off our character sheets, which were vague at best, and our experiences. Some tidbits, if I may;
Confirmed races are Human, Elf, Dwarf, Halfling, Half-Orc, and Tiefling. Classes known are the sacred 4, as well as Warlord and Paladin; more are assuredly to be included.
There are no Fort/Ref/Will defenses or saves; instead, spells and effects seem to call for simple ability saves; Con saves, Dex saves, and Wis saves obviously, but there also seem to be Cha saves against effects.
Skills seem very 2e I think, no obvious ranks, but class-based training seemed to be present for things like Bluff, Stealth, etc. Seemed very rough and unfinished.
Basis seems quite obviously 3.x largely, with some 4e semi-compromises worked in. Dying, for example, seemed like a vicious monster of 3e/4e hybridization.
AND... go.