In Windows 7, the menu bar is hidden by default, that's why no one uses it. Also, "no one uses" those other commands only because no one knows they exist now. The whole point to the new UI is to change things to be better.
Small nitpick: "Burn" doesn't show if you click on the main options of the left tree ("Favorites", "Libraries", etc).
I find it interesting because it clearly shows something changed on the last couple of years, we still remember how important burning something was, right?
If you don't have anything selected you only get Organize and New folder. If you select a PDF you get Open with X, Print, and E-mail added.
Because every file can technically be "burned" when you have a CD burner it shows up all over the place.