AdWords can be dangerous
We had a client who ran an AdWords campaign over the holiday shopping season without monitoring his campaign closely. He got a ton of business from the effort, and was thrilled, until he looked at the cost of ALL of the clicks he was paying for, and did the math with the orders he actually got. In the end it turned out he lost money on every sale. He got the traffic, and he got the sales, but the final accounting showed that he had a completely unsustainable method of getting his sales. To use AdWords successfully you have to pay close attention to the ROI. Here's a great article form the NYT that reviews the potential pitfalls of using AdWords:
