So where's the thing in 5e that would grab me the way skills did? (Or any number of other things)? Where's the basic mechanics that tie D&D together and make every playstyle possible? I haven't seen them. Again, don't care about which classes they include or how feats are selected or that kind of thing. I don't see the one big thing that makes the rest of the game worth buying.
From my perspective (some of these might have been there already in 4e but I don't know), there are these:
- built-in modularity
- coexistent basic & standard characters
- largely simplified combat rules
- general focus on ability checks
- bounded accuracy, and the implications on using low-level monsters longer
- skill dice
- subclass groups (but they are missing some for Barbarians, Rangers and Fighters)
- largely simplified wildshape rules
- no assumption on wealth level and magic items
- many new rules for spellcasting (preparation, rituals, cantrips, concentration)
- saving throws as ability checks (if only they would have more Str/Int/Cha ST...)
- backgrounds
- short rests
- exploration rules
The second point to keep in mind is that it's counterintuitive for a free playtest to closely resemble the final material, since too much similarity eats into sales. While there will obviously be early adopters, WotC does not want the people who are anticipating Next to hear that it's 99% the same as the final playtest packet, causing them to think "oh, well I can just use the rules I've got, maybe make some changes myself to approximate what little the official rules did change, and that's good enough."
I don't know how likely this will be, but if they go with a public SRD like 3e, effectively this is no problem because it means the playtest rules really are the draft SRD. The final product is a physical book (can't beat that) with full artwork and plenty of guidelines, examples of play, additional tables/sidebars, and fluff.