I believe that's more where the Explorer will fit in, an Edge/GM Lambda-type crossover with SUV styling/look. If a 7 passenger Edge was made, it would then overlap with the upcoming Explorer, although some may not like Explorer or Flex, so it may be smart to offer a 7 passenger Edge, who knows?
For MKX, a 7 passenger model would make sense to me, since Lincoln's only crossovers will be MKX and T, no Explorer-type gap filler.....which would also strengthen the case for a 7 passenger Edge, since they share most of their sheetmetal. That said, however, with the MCE in '10, MKX is supposed to begin to move away from 'rebadged Edge' styling, so maybe a MKX-7 (passenger) could be it's own product, given the distinct sheetmetal?