An interesting rumor, that surfaced on the daily Marvelite, claims that Marvel's upcoming Hulk animated series will only run for one season, while Avengers Assemble might last a lot longer.
From the source site: "Marvel’s upcoming animated series is looking great, according to our sources. The show is not only been talked about, positively, inside and outside Marvel but Toy retailers have showed a big demand for the show’s action figures, which led Marvel to order a second season for the show before it even debuted. This is the same thing that happened with Ultimate Spider-Man (regardless of how Marvel looked like they made the decision because of the great ratings). So expect Avengers Assemble to run for at least 2 seasons, but word has it that we might, finally, get more than 52 episodes, which means higher chances (or more likely hope) for more than two seasons. Don’t expect to hear the official second season announcement until few weeks after the show’s premiere. "
The site then moves to talk about Hulk and the agents of S.M.A.S.H:
" Unlike avengers Assemble, the negative reaction the show has been getting from both inside and outside Marvel made the company very cautious about ordering two seasons at the same time. A matter that has gotten only worse, by the low, to non existent, demand Toy companies have showed regarding the license. For these two reasons, Hulk and the Agents of SMASH will run for only one season. "
The article then claims this interesting bit of info :
"There are two things i couldn’t confirm: The first thing is that i heard that Hulk and the agents of SMASH season 1 will only run for 13 episodes, and not 26. I will update this story as soon as i confirm the truth about this info."
More at the source.