Adobe may be in no hurry to wind down its huge, aging, sometimes frustrating business built around Flash, but it isn’t dumb. It’s obvious that the future of rich Web sites–especially on phones and tablets–is about HTML5. And therefore it’s practically mandatory that Adobe release an application that lets creative types build such sites–a program that can join Flash, Photoshop, Illustrator, InDesign, and other Adobe products as a standard part of the world’s design toolbox.