It is not really a surprise, but the official announcement came earlier than I expected. Over the last year a group of coders had been reverse engineering the Second Life client software with the approval of Linden Labs. I assumed an open source client would become available in this year, but had not expected it as early as January: Linden Labs is releasing the client software for Linden Labs as open source.
I think it is a good move for Linden Labs, as it allows them to start focussing more on the server side of things and try to solve their scaling problems as well as the long overdue capacity for voice, while they open up the client for the users’ creativity. Opening up is the only way to help Second Life move more towards becoming an infrastructure. It might not be enough, but it is an unavoidable step, given their current state. Next step is hopefully creating a path to more open server software as well.