In many ways, the ad sales industry is a pretty neat example of market forces; while no-one likes spending money on ads, they have to do it, and they know it.
The industry, like any other, is affected by the ups and downs, but these days, it's so sophisticated that the large advertisers can tune, and fine tune, their spend to what they need at a given time.
Most advertisers of any size started reducing spend while bankers were still singing in the trees, and they'll start increasing their spend while bankers are still nursing their wounds.
With big budgets, fast moves mark out the serious players; when a UK confectioner had a major product recall last year, they pulled all their ads, including cancelling sponsorship of the biggest TV soap, within 24 hours. Advertising would have been wasted at best, harmful at worst, linking their name to a potential disaster.
The Internet has so far seen little sophistication, with most major advertisers going through so many intermediaries that they don't know they've been on a p0rn site until it hits the newspapers, and they don't know their clients web site is spamming until it gets a token Google ban.
That is beginning to change; Google and DoubleClick may be the first 'professional' organization of any size in web advertising, but once their marriage proves to be a success (which of course it will), then change may come rapidly.
How will this help the 'little man'? Simple; Google and others currently accept MFA and similar 'legal abuses' on an industrial scale (oh yes they do!); professionals won't. They'll be looking for targeted audiences and quality sites. They don't want damaged goods near their products.
I don't see any bubbles bursting - but I think the current R******* will incentivize advertizers to be looking at low unit costs (the Internet), real time response (the Internet), accurate response measurement (the Internet) and the ability to revise a campaign quickly and cheaply (the Internet).
I've been wrong before, back in 1973, as I recall. ;)