Slightly off topic, but why is there no high level roadmap for changes like this? It would be nice to see a gantt type chart showing releases and major changes

Slightly off topic, but why is there no high level roadmap for changes like this? It would be nice to see a gantt type chart showing releases and major changes like this that would affect user experience. I asked this question on superuser but got no replies. http://superuser.com/questions/885625/is-there-a-high-level-roadmap-for-chrome-development http://superuser.com/questions/885625/is-there-a-high-level-...