Ever wonder just how much money gets poured into the internet advertising market every year? Here’s your answer: the Internet Advertising Bureau estimates that $21.1 billion was spent on web advertising in the United States alone during 2007. That number represents a 25% increase over 2006. Globally, we’re looking at overall revenue in the $45 billion. That’s a whole lot of money, yet it only represents 7.4 percent of overall worldwide advertising revenue, which is valued at around $600 billion. That’s a lot of cashola flowing through the ledger books, right? Right.