I dont' really like the nikon 28-70. It's really fat, and IMO the crinkle coat is ugly. Also 28mm isn't really interesting. 24mm is borderline.
I dunno, i'm prejudice. i can't really see myself owning a midrange zoom unless all i shot was weddings. They're just so...standard. If i'm going to have something in the standard just-barely-wide-angle to just-barely-telephoto area, i'd want it to have a faster aperture than f/2.8 for sure, even if it means carrying a few lenses. I'd rather have a 24 f/1.4, 35 f/2, 50 1.4, and 85 f/1.4 instead of a 24-70. the lenses would be sharper, faster, smaller, and less obtrusive and alienating to other people.
IMO a better approach if you're into zooms would be a 16/17-35, 50 f/1.4, and 70-200. That way you spend potentially less money, have the same range, faster in the middle, and can go much wider.
This is one of the few topics that i agree with Ren Kockwell on.
If i'm going to have a midrange zoom, it would be on something small like a Micro 4/3rds camera where the purpose is little more than snapshots.