Nick Aster at TriplePundit offers a useful quick summary of an article in Popular Mechanics on "How to Fix Wind Power." I enjoyed the article, which I think is a definite cut above average.
With respect to the obstacles, a few comments (quoting Nick here):
1) Cost of transmission lines from relatively remote locations where wind is best. Solution: Small, local turbines, including personal sized ones that augment the grid with diffuse power generation and negligible transmission costs.
Transmission certainly is a major issue that has to be sorted out in the U.S., not only for wind, but for other electricity sources and to strengthen reliability of the entire utility system. This is a long-standing problem for the electricity industry that is gradually making its way higher on the U.S. energy policy agenda. "Small local turbines" sounds appealing, but while small wind turbines definitely have an important role to play in energy supply, they don't really work when one is talking about, say, providing a sizable chunk of New York City's electricity with wind.
2) The inevitable windless day. Solution: Hook up generators to batteries that store electricity for peak demand and low wind conditions.
Storage is tempting as a panacea. However, most utility systems in the U.S. have little need for specific storage dedicated to wind, and such dedication would dramatically increase the cost of wind. On windless days, utilities use other power sources, just as they do when, for example, a nuclear power plant is producing zero electricity due to scheduled maintenance. With regard to wind's variable output, a simpler answer is already provided above--more transmission lines and linkages. This boosts overall reliability while making balancing problems easier all round.
3) Difficulty of offshore construction. Solution: This is a tricky one, involving technology that's not yet here at as-yet unknown costs.
Offshore construction is definitely something that needs to be addressed. America's onshore wind resource is huge and we can do a lot with it, but to take clean energy to the maximum, offshore wind must be a component. Here's more info on a great recent study on offshore wind in the mid-Atlantic states.