With the OGL tied more closely to D&D, how would that impact the future impact of games like Spycraft or Mutants and Masterminds – games that in 3e used the core d20 concept but diverged radically from D&D?
The new version of the OGL isn’t as open-ended as the current version. Any 4e OGL product must use the 4e PHB as the basis of their game. If they can’t use the core rule books, it won’t be possible to create the game under this particular version of the OGL.
Future versions of the OGL, including a 4e d20 Modern version, may make certain games possible where they weren’t before.
Now that the OGL details have been announced, past d20 publishers are announcing their products for fourth edition. They mostly sound like update products rather than anything ground breaking. More of the same. Yawn. As a store owner, I won't be falling into the trap of buying past D20 products updated to 4E. In fact, unless I see some huge appetite for all things 4E, I'll likely choose to pass on third party D&D products, much like we do now with D20 being dead.