There's no indication from that that you'll see a Linux or OS X port of Visual Studio. They might, but they haven't said that.
This Community Edition is extremely similar to the Express Edition, except with some limitations removed (e.g. extensions enabled) and some new limitations added (5x team members max, which the Express Edition doesn't have: no limit).
The Express Edition can be used to produce and publish commerical software. It says so right on their home page [0].
Still great news, even without a port of VS to OSX or linux.
Personally I'm perfectly fine with using a windows PC as my development station, as long as I can create cross platform .NET code.
Extensions enabled on the community edition is great news for people who can integrate awesome tools like resharper
I've always missed the power of visual studio when programming for open source platforms. This can change things a lot.