Probably a battle between Neverdie-atron, Assitron and Past-His Prime. Likely the Allspark will be replaced by Allstate, and Voltron will join them but actually be a Chevy Volt, made up of an Aveo/Sonic, and a Geo Metro and a Vega (all stellar GM ideas
). So in a couple of years, if the Volt is still around, they'll probably have a Volt Transformers Edition to try and get people to buy them.
A TF4? Milking a dead cow. Let's move on now.