I'm sure everyone will be posting and talking about WotC's announcement of playtesting for 5e (and the New York Times article about it.) (EDIT: I wrote this post before I read the blogs, so I can confirm: everyone is talking about it. The best round-up to date is this list by Tim Brannan.)
What WotC does, of course, is not all that big a deal to me or to other OSR gamers. But I'd like to quickly point out that one of my personal goals with Liber Zero (quickly becoming the central goal of LZ) is to strip the game down to easily-memorizable elements so that the game can be played without reference to books, whereas the WotC goal (and late TSR goal) is the opposite: define as many elements as possible in as much detail as possible to create official resources to be used during play. There's certainly a bit of business-exec-think behind that decision (create as many products as possible,) but I think there's a lot of hobbyist publishers who think the same way, for non-marketing reasons. They think RPGs need to be strict, rather than loose. And it's going to be very hard for WotC to appeal to both extremes of gaming and "unify the tribes" again.
Just about the only way I can see of WotC accomplishing this goal of creating a core game that can be expanded to meet the needs of those who prefer 4e, those who prefer 3e, those who prefer AD&D, and those who prefer OD&D, as well as weird variants, is to make the core game truly core. Not "core" in the sense that the multiple, big books of 1e and 3e were core, but truly stripped down. What you have in 3e, for example, is a character built by setting ability scores, selecting one of 8 to 12 classes, selecting one of several races, selecting skills (weapon and non-weapon proficiencies, in AD&D,) and selecting feats. But if OD&D players want to play OD&D with 3e rules, they may have to drop skills and feats to get the right experience, because they aren't core. And they may even have problems with some of the classes, or the way races are written, because they're designed for more elaborate needs, not core needs.
What WotC needs to do is not write a game book with a substantial number of classes and races (selected according to popularity,) plus skills and feats, and later publish supplements that add more of each. Instead, they need to write a game book with minimal classes and races, selected so that they illustrate how classes and races work, and define simple ways of accomplishing stuff, but with no skill system or feat system... THEN publish a skills supplement that introduces an optional system, and publish a feats supplement that introduces an optional feat system, and other supplements: a class book, expanding the way classes work and detailing how to modify the original classes; a race book, doing the same for races; alternative magic systems; alternative experience and challenge systems that emulate different styles of game; and of course alternative settings. You can even have multiple class books, geared not towards "power sources" but towards different approaches to using classes (heroic classes with a couple extra abilities, epic classes with 4e-style power trees.)
This makes the core rules much smaller and the supplemental books more numerous, but it also makes the whole thing more modular, especially if the setting books and the magic system books do not depend on the skill system or the feat system. You can have old school players buying just the core book plus a point-based psionics-style magic system book plus a setting book, to meet their specific needs, and new school players buying a different set of books to meet their specific needs.
Of course, WotC will not do this. Despite all their talk about making the game modular, the execs are absolutely terrified that they won't sell as many books as they could. What if someone buys just the one core book and makes up their own setting? Never mind that other people are buying many more books; you're losing a sale!
(EDIT II: ... And before my scheduled post went public, someone else also suggested that a core book needs to be more core. Although I don't think he'd agree with me about putting the entire skill system in an optional book. I guess that makes me "hard" core.)
(EDIT III: Another Hard Core D&D proponent: Jason Vey of Elf Lair Games.)