...You are a terrible person. Playtests are the best things ever, and this is a great spread. Wizards, do not listen to this crazy person.
Begrudgingly, I'll admit I'd like more articles on the results of playtests, like official revisions of both classes so far for people playing them.

Consider the playtesting at this point to be a beta test; these PH2 mechanics are primarily completed now, and the purpose of the playtest is to put these new mechanics through their paces, to see if there's any major breaking points which have been missed. That said, I don't expect to see public playtest material for every new mechanic; there's plenty of additional playtesting going on behind the scenes, so to speak.The thing is, the book (PHB II) will come out in march, and it'll probably go to print sooner than that (say, mid february, I honestly have no idea).
We can't really playtest something if it's not going to be changed between now and the time they publish the book.
The barbarian and the bard already got some love, there's still 6 classes to go. Now Druid, Invoker, and Mercykiller (whatever that means).
We're missing another 3 (or 4 if Avenger =/= Mercykiller), though, they might as well not give us the other ones until the book arrives.
But in order for them to tell us what are the changes they're doing to the class based on the feedback from us, they (and us) need the time to do so.
That being said now, do you really think there's going to be any more of those articles? I'd say either they'll throw up all the last 3 ones for january, or possible a single one, or most likely none. So I take it much like some sort of a christmas present.
Although I do agree that it could get a bit overwhelming 3 new classes to playtest.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.