Google has announced that it signed a new pledge, pledging to not sue users, distributors, or developers of open-source software that may violate Google's patents. Google believes in open systems and will only sue if attacked by the group first. This is a big win for open-source developers everywhere.
The pledge is called the Open Patent Non-Assertion Pledge (OPN) and promises the following: "we pledge not to sue any user, distributor or developer of open-source software on specified patents, unless first attacked."
Of course, Google hopes that other technology giants will follow in Google's footsteps. Twitter, though not mentioned by Google, has a similar patent pledge. Twitter's is actually slightly better as it leaves control of the patents in the inventing engineer's hands.