So in Final Crisis, Bruce Wayne 'died'. The media, the public and many readers went crazy.
But those very clever few who were paying attention realised the Omega Sanction that Darkseid uses on Batman in Final Crisis #6 doesn't kill. Instead it is used to punish and remove the person from reality.
The rays of energy transport the target into a series of successively worsening alternate lives, as shown by Grant Morrison in the Seven Soldiers: Mr. Miracle miniseries in 2005-2006, and stated plainly by Darkseid in Final Crisis #6.
At the end of Final Crisis, we see a figure in a cave with the dead body of Anthros. There is the utility belt draped over Anthros and the figure is painting a Bat symbol on the cave wall. In Red Robin, Tim Drake has already found these symbols.
Sonny Sumo was hit by the Omega Sanction. He ended up in a 'Lateral Universe', living out a life in feudal Japan. Eventually he fell 'through a hole' in this lateral existence and returned to his original state. This was also covered in Final Crisis.
Bruce's body was left at the end of Final Crisis, but it isn't really Bruce. He exists in different eras of time and can fight to remember who he is and return to the present day. This is evident in Blackest Night, where Bruce is reanimated to unnerve the others - an 'emotional tether' - but is released after the black rings enslave the rest of the reborn heroes. Black Hand refers to him as Bruce Wayne in quotation marks, revealing that he and his master Nekron know that this isn't really Bruce's dead body.
This isn't a cheat. This isn't a comic retcon. This was always Grant Morrison's plan. Both Marvel and DC have killed a big character and brought them back in short order, but both stories seem carefully planned to me, rather than contrived. This is not the sloppy ham-fisted writing of yesteryear, though I appreciate it may seem hard not to feel a little cheated if you have been reading comics for many years.
The Return Of Bruce Wayne is a six-part series, with a different artist on each issue. Each issue will showcase a different version of Batman, as Morrison pushes him through the various quantum possibilities and comes back to his Bat-family.
With Dick and Damian firmly established as the new Batman and Robin, this may not mean Bruce returns to the cape and cowl. Maybe he'll become a Bat-General overseeing Batman, Robin, Red Robin, Batwoman, Batgirl, the Outsiders, etc. from the Batcave. Bruce's analytical mind may decide a step back is required to see the bigger picture and avoid events like Final Crisis. Alternately he may become Batman again, there have been multiple Flashes and Green Lanterns for sometime now after all.
Who knows? I trust Grant Morrison's writing of Batman. I didn't care for Final Crisis personally, but his take on the Dark Knight has been superb.
Batman: The Return Of Bruce Wayne begins in May.