It's incredible but true: Mark Waid is returning to The Flash! His work on the series is legendary. A lot has happened in the DC Universe since the acclaimed writer's departure from the title, however, and Bart Allen's stunning saga in the pages of The Flash: The Fastest Man Alive has all but guaranteed that, despite a return to the previous volume's numbering, things will not be as they once were. Wizard has posted an interview with Waid regarding the various factors that brought him back, and he hints at the new directions he'll have the crimson comet pursue during his continuation of The Flash.
"I’m saving most of the new stuff for the first issue of the regular book... All I can do is be true and faithful to how I perceive the characters. All I can really do is try to make something interesting out of [the Flash's] new status quo and try to give you stuff that you’ve never seen before in a Flash book."