If your plans are to shop (and walk) the Magnificent Mile then the Hilton Chicago (a grand old hotel with a lot of history) is probably too far south. The Palmer House (an old hotel with an impressive lobby) and the Wit (trendy) are loop hotels that could be considered just off the south end of the Magnificent Mile. The Conrad (good hotel, never had a bad stay, more trendy than impressive)is next to Nordstroms and basically on the MM and may be the best Hilton choice for shopping but doesn't really have a wow factor. The Drake is a old hotel that isn't as is good as the others anymore, imo.
Map for Magnificent Mile hotels can be found here:
http://www.themagnificentmile.com/im...eHotel2011.pdf
Map for MM shopping here:
http://www.themagnificentmile.com/im...Dining2011.pdf
Magnificent Mile info here:
http://www.themagnificentmile.com/