This is absolutely huge for a number of reasons. LiveJournal is the largest open source weblogging system, and one of the largest open source projects on the Internet. This means that anyone can take LiveJournal and modify / run it for themselves at no cost, but how will the potential acquisition affect this? LJ runs its own commercial servers, bringing in a couple of million dollars a year, with 5.5 million users. They’ve always claimed to never really have a business plan, while Six Apart is much more of a serious company. I can see them quietly moving the project away from open source.