Erick Schonfeld had written an interesting article about "The Terrible Cost Of Patents" at TechCrunch.
* We are in the middle of a patent bubble.
* Technology companies are spending billions of dollars on assets which they need primarily to defend themselves against the rising tide of patent litigation, they won't invest in new products, new jobs, new facilities or other economically productive activities. And by and large, they will not use those patents to create new products.
* What you and I might consider an improvement, a patent lawyer might consider infringement.
* Patents were originally conceived to protect inventors—people and companies who contribute to the advancement of society by creating new products. But in the past decade, something went horribly wrong. Patents are increasingly became nothing more than financial and legal weapons, to be amassed in portfolios by "non-practicing entities" (i.e. patent trolls) and used to extort protection money from economically productive companies.
More info from PricewaterhouseCoopers full pdf study "Patent litigation trends 1995-2009 and the impact of recent court decisions on damages."