The newsletter DC Comics Direct Channel #914 identifies the contents of the upcoming Flash Presents: Mercury Falling and Flash: The Human Race trade paperbacks.
May 2009: Flash Presents: Mercury Falling (Todd Dezago, Ethan Van Sciver) will collect Impulse #62-67. That covers the 5-issue story arc itself as well as the one-issue epilogue guest-starring the Justice League, Justice Society and Young Justice.
June 2009: Flash: The Human Race (Grant Morrison, Mark Millar, Paul Ryan, Pop Mhan) will collect Flash v.2 #136-141 and a story from Secret Origins #50. The Flash issues cover both “The Human Race” and “The Black Flash.”
The Secret Origins story is undoubtedly the retelling of the classic “Flash of Two Worlds,” (Flash v.1 #123) in which Grant Morrison figured out how to incorporate the parallel-world story into a single-world setting. Unless I’ve forgotten something, this volume and Flash: Emergency Stop will cover all of Grant Morrison’s Flash solo work.
It also lists the Final Crisis hardcover coming out in June, along with the Final Crisis Companion trade paperback, which includes all the FC one-shots (including Superman: Beyond, which started as a one-shot that just got too long.) No word yet on when Final Crisis: Rogues’ Revenge will be collected, but there are supposed to be more summer 2009 announcements later this week.