The Mozilla Foundation has announced its process for updating the Mozilla Public License. While Mozilla's substantive goals for the new version of the MPL (which will probably be numbered 2.0) are quite different from the FSF's objectives in drafting GPLv3, Mozilla is adopting some of the features of the GPLv3 process, including a series of public drafts accompanied by rationale documents, the use of a collaborative commenting system, and a general commitment to engaging the license-using community in contributing ideas and feedback.
Although it is one of the more commonly-used FOSS licenses, the MPL has a cultural and historical importance within FOSS that is greater than the mere number of MPL-using projects would suggest. The license is closely associated with one of the most vibrant and influential free software project communities, although most Mozilla projects actually use the disjunctive "tri-license" of MPL 1.1, GPLv2-or-later, and LGPLv2.1-or-later. Along with its obsolete sibling the Netscape Public License, the original MPL was, I believe, the first non-GNU copyleft license. Stylistically, it departed from earlier free software licenses by drawing on commercial software license drafting traditions. It was also one of the first free software licenses to address the software patent problem through the use of patent license provisions.
On a more negative note, the MPL (through no fault of its own) spawned a large set of derivative licenses during the early 2000s, some of which were non-free and most of which were corporate "vanity licenses" that are best forgotten. (The one exception is Sun's CDDL, an important FOSS license that improves on MPL 1.1 in certain ways.)
I am looking forward to participating in the MPL updating process by providing feedback and suggestions to Mozilla, and I encourage others to get involved as well. Mozilla benefits from having a knowledgeable and talented team that is steering the process: Mozilla Foundation chair and original MPL author Mitchell Baker, Mozilla lawyers Harvey Anderson and Luis Villa, and longtime Mozilla hacker Gerv Markham.