Wizards has released a new version of the Game System License here. Reading it over it appears that they fixed many (but not all) of the issues with the first version. The two most important are the removal of Section 6 the poison pill clause involving the OGL, and the fact you can now send in a notice of termination and get a 6 month grace period to sell off your stock.
One of the bigger outstanding issues is that you still can't copy any statblock or description from the core books. This means effectively you have to create all new content if you want to publish an expansion or a module for 4e. This hasn't changed from the first version. I will say that what been published by 3rd parties so far has many of the classic monsters renamed and changed in trivial ways.
Clark Peterson of Necromancer games has announced he going to start work on a project called 4e Classic. One advantage of a exception based rule system is that you can easily change the feel of the game by changing the powers. Clark intends to do this to produce a version of 4e that plays and feels more like 1st Edition AD&D.
Is the new license a good thing? Sure it will cause many that have been hanging back to publishing again particularly Necromancer Games. It not as good as the OGL which is sad. Some publishers will continue to avail themselves of the fair use doctrine. Most others will continue on an independent path like Paizo and Pathfinder.
The big news for this industry, sadly, is going to be the impact of the deepening recession. It still too soon to see how it plays out.