Feedback portal: http://feedback.telerik.com/Project/153 (in progress filter)
Upcoming features (not internal builds): http://www.sitefinity.com/developer-network/forums/upcoming-features
I want to see a roadmap too, but they just aren't obligated to. Internal builds are just minor features and bug fixes, you aren't going to see real 'roadmap' stuff appear there fyi. The op was being snarky implying they were being lazy, I'm mearly saying there might be other reasons why, and there are other avenues to see whats going on.