My experience
I've been in marketing for the past 14 years. I fell into a receptionist position at a local advertising agency and went on from there. Mostly I've worked in print with a short stint in TV, some time with promotional products and, of course, my radio time. I believe the client comes first. I'm not going to sell something to a client just to make a buck. If I know it will not work, I'm going to say so.
Every media has it strong and weak points. From cost to effectiveness to longjevity to r&f. Everything can be used effectively, it's just convincing our clients which ones are the best (ours of course).
Oh, and don't try to get me to badmouth any other medias or companies in marketing. I love it all. I am a marketing person, not a sales person.