Look. Dave is a good drummer, I am a good drummer, there are lots of good drummers, and I would go out on a limb and say that 99.9% of the drummers on the planet want to play with Led Zeppelin. Just that most are not as famous as Dave.
So he is the one that makes the headlines/blogs, reports, whatever, so it's going to continue...
Jason is the only drummer that is going to play in Led Zeppelin (I am pretty sure of that).
If nothing else, these Grohl stories are one more issue to keep Zeppelin in the media, and thats ok by me. (not that I am anyone, but a fan )