There's a lot to learn about the trends. The involvement of Judge Posner of Chicago is especially notable IMO, due to his libertarian views.
Perhaps MS is changing its behavior due to the change in the legal environment, but I've read other stories that attribute the change to pressure from customers for products to interoperate. I wonder how you would rank the two forces as far as their influence on MS's behavior?
A posting on the Groklaw site gives some more discussion of the widespread dissatisfaction with the patent system. It's a good starting point for learning more about this. See http://www.groklaw.net/article.php?story=20040703041613818
Calls for patent reform are coming from all sides. The above article mentions the Electronic Frontier Foundation, Federal Trade Commision, National Academy of Sciences and Hewlett-Packard. (The dissatisfaction spans the political spectrum.)