There might be a chance that you, and your advertisers are undervaluing your traffic. As an economy, the internet is still young, and in any market economy, it takes some time for the Invisible Hand to adjust supply and demand. Bryan Eisenberg at ClickZ.com thinks that the value of online traffic is undervalued because it is underpriced. As Eisenberg explains:

This relatively new Internet economy is settling into familiar patterns, and the costs of doing business online are beginning to resemble those of our brick-and-mortar brethren. In the brick-and-mortar world, there's no such thing as low-cost traffic.
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Most companies simply don't have the capital or means to attract natural traffic flows. As in the brick-and-mortar world, they must work a little harder, advertise more, and otherwise make up for their lack of location.
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Online businesses make up for less desirable locations by advertising. They rent high-traffic retail space in the form of paid keywords. Demand increases prices. Short term, online traffic remains a value compared to mass media. Soon, though, online traffic will rival, if not exceed, the cost of offline advertising.
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Compared with offline retailers, some online retailers get traffic for pennies on the dollar. Is it any wonder they treat traffic as something worthless? They simply don't value it.
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Traffic-cost inflation will be good for the industry and the consumer. It will sort out average marketers from the exceptional ones, just as it does in the offline world. Exceptional marketers will begin to treat traffic with respect.

Indeed, to think that any aspect of the e-market will not undergoe some significant shifts over the next decade is extremely naive. The market is still too young to have been groomed by the invisible hand. In fact, we are already seeing the emergence of a number of specialized affiliate programs that understand the traffic of their niche best.

For example, once upon a time, PPC adservers such as Google AdSense were the only options available to bloggers. Now, companies such as BlogAds is just one of the several affiliate options available both to bloggers that want to monetize their traffic as much as possible, and advertizers that want to reach out those kinds of users. Successful bloggers know that their traffic is worth more than 2 cents a click, and advertisers are willing to pay flat-rates to rent a banner or button for a pre-determined length of time.

Via Search Engine Watch.