So, before I jump into the classes themselves let me take a look at the DM packet. It's much shorter than the player version and mostly covers the same material, just from the DM's perspective. So I'll just comment on the things that stand out:
First we've got the DC List of different difficulty classes ranked by how hard they are. Right off the bat I see an issue with the fact that DC 10 is "trivial" and it says "An adventurer can almost always succeed automatically on a trivial task". Now, that's just not true. DC 10 is certainly low but (especially with the smaller modifiers) it's harder near-automatic. It's about a 50/50 chance of success for someone with an average ability score and it's still around a 30% failure chance for someone with a good (+2 or +3) bonus. Seems like DC 5 should be "trivial".
There's also a standard set of rules for hazards (if you fail a check by 10 or more and there's a chance of something bad happening, it happens) and for when checks can be "automatic successes", which seems pretty rare unless there's a lot of modifiers floating around that we're not seeing yet (it requires a bonus of 5 higher than the DC).
Next we've got some generic advice on when to roll dice, how to engage players, etc.
A few rules on what constitutes an "action" in combat (notably things like drawing weapons are no longer actions, not a bad choice) and letting us know that you should always round down.
A few notes on creature sizes. There's an odd mechanic called "fills" which represents how many medium size creatures a large creature counts as for purposes of surrounding another creature. likewise there is an entry for how many medium sized creatures can surround a larger creature. This seems like it's meant to allow players to play easier without a grid, but ultimately it seems pretty unnecessary and certainly more fiddly than needed. I don't think we really need to calculate exactly how many collossal creatures can surround a single medium sized creature. Isn't anything more than 2 overkill at that point anyway? Not to mention that it neglects things like reach and the myriad of bizarre body structures available to D&D monsters. Makes me realize that there's no "flanking" or "back attack" rules so far. Of course I can guess what they would do...give you advantage of course.
Now there's a bit about lighting levels. It mentions being "lightly obscured" and "heavily obscured" but beyond a mention in the player's guide about how you normally have to have "heavy obscurement" to hide there's no indication of what effect these two conditions really have. Perhaps that's all there is?
Next we get a big list of common tasks. This definitely supports the idea that bonuses are going to be smaller. In 3e/4e most DCs were measured in increments of 5's but here it seems like increments of 2. I definitely feel that cluttering things up less with loads of modifiers is a good thing, although I note that this seems like it'll definitely make things a bit more random. Someone with a +5 bonus is capable of some very impressive feats...but is also extremely capable of failing even the "trivial" tasks.
Notably missing from the playtest document is how to handle falling damage. It's a very minor thing obviously (and probably going to be the same 1d6 per 10' it's always been) but it's something that's likely to come up in just about any game.
I'll get to the classes on my next post, but before that I'll skim this bestiary included as well. Let's see...
First impression is that this reads like a hybrid of the 2e and 3e beastiary...with just a smattering of 4e in some of the critter's unique abilities.
Just to dissect one completely:
Creature types: We've got 3e's beasts, humanoids, oozes, etc. That's a good thing, they provided an easy way to "sum up" common critter attributes, and I approve of their continued existence. It also looks like we're seeing the return of the "3x3" alignment grid. I could take that or leave it. I know it leads to endless flamewars but personally I've never found it impossible to ignore. No sign of 4e's "critter roles" like Brute, probably for the best.
HP: We've got just a generic hp entry, no HD. Huh, even 2e had more info than that. I'm not sure how I feel about that. We'll see, could just be a simplified-for-playtest thing. Noting that while many of the minor, yappy monsters have tiny hp amounts some of the big guys do have loads (ogres have 88 hp and minotaurs have 130. wow!)
Ability Scores: A full set of ability scores. This I definitely approve of, it was the best thing 3e ever did to monsters. I'd be very disappointed if they stepped backwards here.
Space, attacks, reach and all the rest seem totally standard for 3e. One difference, a static XP value rather than a CR. Hmm...on the one hand CR was almost completely useless when it came to calculating actual challenges...on the other hand XP is almost certainly not going to be any better and it seems to preclude useful things like templates.
I'm overall ambivalent here. On the one hand I'm seeing a lot of good stuff, but that good stuff was mostly taking whole from 3e and doesn't involve anything new. On the other hand the lack of HD and the static XP value seem like they're going to make customizing monsters very difficult. Easily customized monsters were a huge benefit in 3e. If you wanted to make an ogre shaman or a crazy goblin alchemist all you had to do was slap on a few class levels or if you wanted something weird just lay on a few templates. One thing I definitely didn't like about 4e was the way that every single creature seemed to have 5 different variations, bloating the monster manuals with needless extra versions of the same damn thing. Just give me one, generic monster and the tools to make it unique if I need to.
That said, I do like some of the abilities I'm seeing in these creatures and some are fairly unique. I especially like the evil cultist's ability to summon tentacles of darkness when they're near an evil altar. That's a legitimately neat ability and one that only makes sense in the hands of a monster (rather than just taking abilities available to players and applying them to a monster). So for now I'll reserve judgement.
I will say that from what I've seen so far that I definitely prefer 3e's poison rules, represented mostly by ability score damage. Generic "poison damage" isn't as interesting or useful, although I can certainly understand that it's more complex.