In only 6 years, from 2000 to 2006. wind energy has become a significant resource on many electric utility systems, with nearly 74,000 MW of nameplate capacity installed worldwide at the end of 2006. Wind energy is now "utility scale" and can affect utility system planning and operations for both generation and transmission. The utility industry in general, and transmission system operators in particular, are beginning to take note. As a result, numerous utility wind integration studies are being conducted in the US under a variety of industry structures. This paper will summarize results from a number of case studies conducted recently in the US, and outline a number of mitigation measures based on insights from the recent studies.