I just rode one of the new space age Green Line Ts yesterday. They just seem wrong because they are actually modern. They also have a digital sign inside, displaying the destination, much like the Red Line. And the conductor is actually intelligible.
The new ones have a sunken middle, with the ends raised in the middle. There is also an extended middle section with seating, between the two sections of the trolley.
The sunken middle also allows for handicapped access, and there is an area for wheelchairs to lock themseleves in.