The Comics Continuum contacted Al Gough, the executive producer of 'Smallville', and asked if there would be a spin-off featuring the superheroes who appeared in the recent episode "Justice".
"No plans for the moment for a Green Arrow spin-off. Sorry," Gough said in response. "No plans to bring the entire Justice League back this season, but you may see several members toward the end of the season!"
So as it stands now in that alternate dimension (shared by 'Smallville' and 'The West Wing'), Green Arrow, Cyborg, Aquaman, and Impulse (who should be called Flash, I'm sorry!) are off on their quest to shut down Luthorcorp.'s secret project known as "33.1".
One thing that wasn't addressed in the episode was that Aquaman had undergone a change in his physical appearance. If I'm not mistaken, this was the third alteration. (Although his second "regeneration" was in the unaired pilot - but which was available for viewing online. That actor is now playing the Green Arrow in the show! Such headaches for the televisiologist!)
In the real world, of course, the reason is due to recasting. But for that alternate dimension of Toobworld, Aquaman aka "AC" may have been exposed to the equivalent of the theoretical meteor that altered the appearance of Ginger Grant of 'Gilligan's Island' in the main Toobworld.
If that dimension's version of the island also sank beneath the waves, that meteor might have poisoned the ocean's waters and continued to affect human physiology once Aquaman got too close to it.
Just an idea for now, and as it's all part of a different dimension from the main Toobworld, it's not really a high priority at this time.