Friedman is one of the worst sources of opinion I've ever read. The World Is Flat (which is, admitedly, his only substantial work I've read cover to cover) is filled with unwarranted conclusions and groundless generalizations and altogether horrible metaphors. I've learned to just tune out when he's mentioned.
I found The World is Flat to be a useful insight into conservative economic thinking. I also interpreted it as an attempt to persuade the conservative political and economic base to take a more global look at their activities using their own language, rather than as an accurate treatise on globalization.
In that context, I was able to get past his obeisance to the corporate superpowers of America and his other inaccuracies, and see points that may be valuable. Even though I frequently disagree with their opinions, Friedman and another conservative, George Will, are two of my favorite editorialists. Maybe the fact that I'm neither liberal nor conservative contributes to my enjoyment of their writing.
yea really. the original story cites him as a middle east expert... who cheered and approved of the invasion of iraq. now that's a record to be proud of.
EDIT: i do agree with him though that the US should invest in sustainable energy.