Basically, my possibly buzzword-influenced perception is that since more people listen to blogs and other highly grassroots, internet-based, relatively honest (to the extent that they know anything) sources of information, classic marketing has begun to wane in effectiveness, because marketing most of the time is dishonest hot air, and no one blogs about that. So if you're a marketing executive, this should not be very consoling, since it means that your reason for existence is beginning to disappear.
Well, I think that your reason for existence still persists, but the methods for achieving that existence have changed. The internet has made all markets more "efficient," so that marketing executives need to figure out better ways to let people shopping for their product/service discover them through search engines, blogs, etc. ...The good news for a startup is that you do not need to have a huge distribution organization to find potential customers in this day and age if you can get good at "modern" marketing techniques.
Markets being more efficient means that customers know better what is actually going on, and marketroids have less influence over their perceptions. Sure, there are still horrid inefficiencies, like the 1000% markup on eyeglasses, but 19dollarglasses.com and the like has begun to close that inefficiency. It isn't that marketing has changed media, like the expansion into TV advertising from radio and paper; it's that marketing fundamentally is waning in effectiveness as people have more ways of communicating honestly as people, rather than as marketing departments.
As a result, the startup looking for potential customers not only doesn't need a huge distribution organization, it doesn't even need to get good at "modern marketing techniques," since most successfully marketed products, particularly on the internet, have succeeded because they were better, not because they used hip new marketing techniques. Even PR is ineffective at penetrating actual blogs, although it still has an effect on old-style newspapers that have been webified.
"your reason for existence is beginning to disappear."
Not the whole reason for their existence. There is broadcasting to the market to get leads, there is manipulating the market and perceptions artificially (which I hope is the part that's dying), and then there is also _reading_ the market correctly- then getting the right information to the rest of the company.
There have always been the manipulators, but you don't have to be one in order to be a good marketing exec. If your product genuinely stinks, move on.
They probably trick some people into believing that they are honest bloggers, but since people reading blogs generally expect and want the bloggers to be honest citizens, incognito dishonest bloggers can't stray nearly as far from blogger-quality honesty as normal marketing can without being yelled at for being a shill.
