At The Simpsons panel at San Diego Comic Con International, Comic Book Resources reports that producers for the venerable animated sitcom told fans to expect a crossover with Futurama coming fairly soon--but after Futurama has been cancelled for good, by the sound of it.
This season is meant to be Futurama's last, but according to CBR, the shows will cross over either in this year's Simpsons season finale or next year's season premiere.
In case that wasn't enough crossing over, Futurama's Hypnotoad was spotted in footage screened at the panel, in a segment from the Guillermo del Toro-directed Treehouse of Horror episode.
Here's how CBR described the announcement:
On the subject of Groening’s other series, the creator made a surprise announcement: There will be a Futurama-Simpsons crossover, with the Planet Express coming to Springfield. Work is now under way, with plans for the episode to air either as this season’s finale or next season’s premiere.
Outside of brief sight-gags, the series have never crossed over before on television (although they've done so a couple of times in Bongo Comics).
How they'll explain the crossover in-story, given the fact that it's been established on Futurama that The Simpsons was a popular TV series in-universe, is unclear. In the comics, they basically skipped the barrier between fiction and reality, not unlike how Golden and Silver Age Flashes Jay Garrick and Barry Allen first met in Silver Age DC Comics.
The Simpsons will also reportedly cross over with Family Guy, Seth MacFarlane's hit comedy that has arguably unseated The Simpsons as the crown jewel of Fox's animation empire.