And no, it won't be one, but three crossover episodes!!
The 43rd issue of Shueisha's Weekly Shonen Jump magazine announced on Monday that the Bakuman. anime and Sket Dance anime will collaborate for three crossover episodes.
Two episodes will run in October, and one will run in November, but no further details about the episodes' release dates or story have been announced. Weekly Shonen Jump will publish the next announcement, including information about the character or characters who will hold the key to the crossover, on October 24.
This could be the start of a new trend in filler episodes, actually.
source: ANN
It seems they are implementing this due to the success of the Gintama and Sket Dance crossovers.
I can't wait till Niizuma Eiji meets Himeko-chan!!