You pretty much need a bit of everything in there ?
From what I've seen Drupal would sound like the way to go
CMSMS doesn't have enough power to handle everything just yet without a good bit of hacking.
the 3 shopping carts you mentioned at the end are just that shopping carts so you don't really get the blog / news / forums aspect with them.
Joomla ... well I just don't like
dotnetnuke I've never used so can't comment on it.
At the moment I'm doing what you're after using CMSMS + zencart but its going to be rather more basic with a lot less posts / traffic I'm assuming.