I still can't believe it. Let me copy the official announcement verbatim.
Broadcom would like to announce the initial release of a fully-open Linux driver for it's latest generation of 11n chipsets. The driver, while still a work in progress, is released as full source and uses the native mac80211 stack. It supports multiple current chips (BCM4313, BCM43224, BCM43225) as well as providing a framework for supporting additional chips in the future, including mac80211-aware embedded chips.
The README and TODO files included with the sources provide more details about the current feature set, known issues, and plans for improving the driver.
Broadcom makes its Linux drivers open-source
Posted on Friday, September 10 2010 @ 18:46 CEST by Thomas De Maesschalck
OS News reports Broadcom has made its Linux drivers open-source: