I have said, "Marketing is not advertising" so many times that I can't begin to tell you how many (usually with a little frustrated indignance in my voice).
Seth Godin just said it better than I ever could - and he embellishes his comments with a poignant clip from AMC's Golden Globe-winning TV show, Mad Men. What we see in the clip looks all sexy and cool, but is just advertising - taking something that exists and promoting it.
All the behind the scenes stuff involving the 4Ps/7Ps - whichever you subscribe to - (and related development) often gets overlooked - but that is the lion's share of marketing.