While reviewing the answers from Costs of Keywords, I was just testing and I typed in search engine optimization. Now that shows something called Advertiser's max Bid. Some are $2.33 and some are $2.01. I am guess that if this particular link showed up & someone clicked on it, the advertiser would have to pay? Now would the advertiser pay $2.33 or something lower? If it is lower, how is that determined / who determines it? Thanks!
Google has a learning center that explains what you pay. It depends on your quality and the competitive bids. If your quality is better than your competitor's you could bid0.40, they bid 0.65 and you rank first and pay 0.37. See link below to make sense of it. http://services.google.com/awp/en_us/breeze/5310/index.html