The third possibility would be that DME will continue to operate and will continue to be complimentary in 2007 and beyond.
DME is a success. According to Disney's 1st quarter earnings report, room occupancy is up, average daily hotel room rates are up, and guest spending is up exactly what Disney was trying to achieve with DME.
If they start charging depends on price. I paid about $90 for towncar round trip which usually got me to Disney in about 30 minutes, with ME it's been about 90 to 120 minutes. So if they charge close to the $90 I'll go back to the towncar.