Warning: spoilers ahead for Justice League #61!
In the latest issue of DC Comics' Justice League, a new power classification for heroes has just been revealed. Following the League's recent addition of Naomi McDuffie to their ranks, Batman seems to believe that the powerful young hero is what he refers to as a "mega-power." This is a new label that hasn't been referenced before in DC Comics, and may be connected to Naomi's origins as well as holding a connection to DC's Infinite Frontier, a new era of comic continuity that just began in the DC Universe.
In recent issues of Justice League from writer Brian Michael Bendis and artist David Marquez, the League have been dealing with incursions by the interdimensional villain known as Brutus. They soon discover that he hails from the same alternate universe as Naomi, which is why they recruited her to join their team. On Naomi's Earth, the disruption of the ozone layer caused an unknown source of radiation to leak to the planet's surface, leading to 29 individuals gaining extremely potent superpowers. While some wanted to rule with their new godlike power, others tried to stop them, and the resulting war led to 14 of their number being killed. Additionally, 7 left the planet afterward, leaving only 8 remaining on this alternate Earth. When Naomi was born to her two superpowered parents, the dark tyrant Zumbado tried to kill her. This prompted them to send Naomi to the Prime Earth just before Zumbado killed them in retaliation.
Now, Justice League #61 sees Naomi going back with the League to her homeworld, which has become an apocalyptic wasteland. However, the alternate Earth generates some interesting reactions from the League members, such as Black Canary and Hawkgirl getting their superpowers amped up, while Superman loses control of his heat vision completely. In Naomi's case, it seems as though more elements to her energy-based powers are manifesting, and Batman confirms to Superman that he believes her to be a "mega-power," a new term in the DC Universe that seemingly indicates Naomi's potential to be a major heavy-hitting hero.
Considering Naomi's background with her homeworld, it seems as though the power she's inherited is just as powerful as her parents' abilities and those of the 29, who were nearly godlike. Perhaps this is what classifies her as a "mega-power?" The term also crops up in the issue's catch-up page - which refers to her as "a new mega-power named Naomi McDuffie" - as well as the solicitation information for the previous Justice League #60. The catch-up also identifies Brutus as a mega-power, so it's possible that the term is going to be used for the heroes and villains of Naomi's reality, but given the way Batman uses it and the fact that Brutus has so far shown himself to be stronger than Superman, it's as likely to be an indication of pure might as anything more technical.
Cleary, being a mega-power seems to be a level above being superpowered in the DC Universe, seeing as how Brutus is able to go toe-to-toe with Superman and Black Adam. While Naomi and Brutus are the only DC characters thus far to be given the classification, it would be interesting to know if there any heroes from the Prime Earth who could be considered mega-powers as well. It certainly seems as though the new label is similar to that of Marvel's omega-level title for its mutants, a classification given to the mutants who are the most powerful and/or most adept at a certain kind of ability above other mutants. In any case, mega-powers certainly seems as though they could be a big part of Infinite Frontier going forward as the Justice League explores whole new dimensions within the new DC Omniverse.