I think in the sequel megatron will have to get an altmode, remember this is also a property owned by Hasbro, and they seem to think that kids attention spans are like 5 minutes, so with that they would certainly need a new alt mode for megatron so they can release a totally different toy, but my guess is Megatron will still have his cybertronian form for the first part of the sequel, that way hasbro can sell off the Megatron's that didn't get sold during the first one..
Remember this is after all a toy company property, and the only reason its being made is to make money..
hence all the changes to the property to bring in the masses, and hence pissed off G-1 Purists..
Not to mention that Story content wise, megatron will want to hide so that he can sneak around and plot evil schemes against the Autobots and the Governments of Earth..
Thast said I could see megatron as few items:
The Stealth Fighter F-117 night Hawk
http://www.richard-seaman.com/Wallpaper ... oClock.jpgThe Mig 31 Firefox
http://www.axeman3d.com/thumbnails/Firefox.jpgRobot Fighter
http://www.axeman3d.com/thumbnails/Mofighter.jpgA good design for Dirge for the sequel
http://www.axeman3d.com/thumbnails/ka65.jpgthe military has been studying mobile Weapons platforms for years and is interested, surprisingly in Mecha and its ground applications so this is a fan design, but its based a little on Military research, the M-12 Mobile Weapons Platform.
http://www3.sympatico.ca/mladenpejic/MWP.htmHere is an interesting Futuristic tank
http://f.hatena.ne.jp/fake-box/20060402195306Or the Russian T-95 Next Generation tank, Wow!!
http://www.salute.co.uk/cms/show.asp?docid=111