From what I understand, they planned to release several episode at a time, usually around school vacations and holiday periods. Which makes sense, considering that's prime time to get that demographic. That was their plan with Turbo, and it seems to be the plan with others. Though, some of the episode releases were a bit random.
Other than that, I'm wondering when other announced series will premiere. I really wish they could have continued Monsters VS Aliens the series via Netflix, but I bet Nick has some sort of ownership of the show and probably the show specific characters.