I think he is refering to the battle at autobot city during the movie.
I too, think it would be great to finish s4 and continue with a season 5. Pleanty of characters who never got to be explored. And we can revisit anyone who wasn't shown to have died. It could even slipt between earth bound autobots (those who have relistic alt modes such as S1 and S2.) and those with cybertronian modes out in space. Then we can go find starscreams body and and let him lead the earthbound decepticons.
or we could just do the new series. surely it will be just as good.