4e: For Those Keeping Score at Home...

Here's where the various third-party publishers have come down on taking part in the $5k, early-adopter grace period WotC is offering:

Necromancer Games is in like Flynn!

Goodman Games also is eager for a piece of the action.

Paizo, in spite of some level of partnership with Necromancer Games, is moving a bit more cautiously. However, I'll be shocked if they don't jump in early.

Green Ronin seems intrigued, but they probably have better things to do with their time.

Mongoose is cautiously optimistic.