Trickster Spirit
Explorer
I used to run playtest games in the beginning, but I stopped several months ago.
At the beginning, it seemed that WotC is aiming for a light ruleset, with fast combat and more narrative focus (today, I'd call it Dungeon World style). I was really interested in it. While the early packets had their weaknesses, they presented a game I wanted to play.
Then, it started to go downhill. Packages introduced more "numbers game", more mechanics-focused (as opposed to fiction-focused) options and in general moved the game further and further towards 3.x style. If I want to play this kind of game, I already have Pathfinder - and nothing I saw in the playtest suggested that Next may correct Pathfinder's problems.
I'm still tracking the changes they make in the playtest and if I see Next moving back to what I liked, I'll be back on board. But I don't expect it to happen.
Actually, I don't think you need to worry so much about this. What we saw in the first few packets was the designers trying to iron out the Basic rules and decide where they were going to go with the game. Mearls has mentioned assigning mechanics "green", "yellow" and "red" ratings depending on the level of acceptance from the playtesters; once the core Basic rules were mostly green, they needed to start work on the Standard and Advanced rules, which are supposed to be much more in line with a 3.5 / 4e level of complexity for players who are interested in that kind of ruleset.
I'm pretty sure that's why each subsequent packet is becoming more complex; the added layers of rules aren't transparent to us yet, so it looks like the "Basic" game has disappeared, but we've just got Standard and maybe Advanced mechanics bolted on to it Frankenstein style while the designers work out how the final product is going to look. When Next comes out, Basic will be available from day one and provide a much cleaner, less-fiddly alternative to PF-level play, and ideally we'll be able to bolt on subsystems from the Standard or Advanced tiers to make our ideal D&D.