I'm Predicting a new trailer and it'll go something like this....
It starts out with SSBM models of Luigi, Young Link, Mewtwo and Game & Watch Running at each other. Then one by one they phase into their updated Brawl Models. Luigi with stylin denim, Young Link gets all Cell-Shaded Looking, Mewtwo has a very slight graphical update while G & W looks the same and makes a silly face. It then shows the four fighting over a number of stages an Assist Trophy Pops up followed by the final smash for 3 of the four fighters....
Cuts to an airship battle where Ridley Flys in ( Newcomer Ridley!) Ridley Pops a couple moves until a Red Pikmin Flyes by. (Newcomer Olimar) Flashes, Olimar and Ridley battle it out, They both turn to see themselves getting Falcon Punched... In rides King Dedede on a star, he crashes into a rock, everyone looks at him as a Crash enemy from the Kirby games crawls out from the crash, Dedede pulls out his Hammer, every gasps, and cut to a seen of a huge explosion going off in the distance.... Then the Smash Logo Flashes...
The Screen Goes Blank for a couple of seconds..... This Screen Pops up:
Dr. Light tells Mega Man all about his invite to Smash Bros.
Then a Clip of Mega Man joining the Brawl.
Thats my prediction and I'm sticking to it!