Yep. The new layout has taken the news off the homepage and everything. I imagine we'll hear every now and again from them on twitter and in the forums and such, but after today, they are officially signing off of Halo (and everything they've done the last 20 years) to continue to work on the next game.
Theres not exactly anything for them to keep us up to date on, or even talk about really, until they're ready to talk about their new project.