(No, it wasn't always open source. But you knew that, right?)

The MTOS project officially launches today. Read Anil's announcement post for some details, grab the first nightly build and start playing. Note that this is beta code, as it leads directly into the release of MT4.1, codenamed "Boomer."

I'll be posting on some of the new tags and changes over the next few days after doing a bit more rummaging around in the template code.