If I had to guess,
4E will pretty much be as open as
3E was, but
WOTC isn't going to just hand over the rules already typed up for free. I believe we'll still be able to use the rules in the same way as before, but we'll have to go through the trouble of typing up our own rules out of the book instead. I'm sure that an enterprising person will likely come along that will do the work for you, if you want to wait a bit, and release the text for free on some website, all in accordance with the
OGL.
The
SRD for
4E is not about restricting the rules you can use, but about keeping people from using the
SRD as their rule book. How many times have you read someone's post about doing just that? I imagine
WOTC has read the same things, and they are taking this approach to handling that particular situation. If you are a publisher, you're serious enough about the game to buy the core rules as a minimal investment. If you aren't, then
WOTC doesn't want to give away their Open Game Content for free.
It's still Open, it just isn't free anymore. Well, at least in the beginning before someone does the work of creating an
SRD site under the
OGL with all the Open Game Content typed out for your perusal.
That's my two coppers, anyway,
Flynn