NYTimes and Forbes are reporting that Facebook is lowering its admission requirements.

The move is meant to help the site expand, but it risks undercutting one of its attractions: it has been more exclusive and somewhat more protected than MySpace, its larger and more freewheeling rival.
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Under its new system, Facebook will create new networks for 500 geographic regions, and it will allow anyone to join them. In the default setting, people in the region — like the New York City area — will be able to see the full profile of other members in the same region. Facebook has long offered a series of options that allow users to expand or contract the information shown to various sorts of people.

I tend to think of openness not in terms of who can join, but what hurdles does one need to jump to access content.  In those terms, Facebook is still a closed community and I think that tends to create an advantage for MySpace.