Second this. There is a significant market for a not necessarily powerful 15".
There is a significant benefit for us (not sure for Apple -- judging by the lack of such a line, it probably doesn't benefit Apple) if Apple were to separate those two directions.
MB Real Pro 15" with no unneeded compromises made for portability and a lighter 15" MB/MBA with adequate compromises made. Most other laptop companies all offer such a lineup and I really hope Apple does the same since their number of models is so limited..
Gaah, I would love that. They could call em MBP and MBP+. MBP can replace the MBA, emphasis on thin and light while still being powerful enough to differentiate from the MacBook, which takes the stage as the true ultra portable in their line. Everything soldered in. The MBP+ OTOH could be the more powerful performer that's a bit fatter with at least some user-upgradeable parts. C'mon Tim, just do it and take my m'fing money, man.