I don't know if this will be helpful since I don't know what exactly your essay topic is, but I think that Weber would say that his analysis still holds true today.

Weber did not say that religion was still the actual driving force behind capitalism in his day.  Instead, he said that previous religious fervor had sort of shaped society.  By his day, he said, people had the ideas (work for work's sake) without really connecting it to religion.

I think he would say that the capitalist ethic has spread now in a way that no longer has so much to do with religion.  He would point out that it has spread, for example, to Japan and even to China.

However, he might argue that a lack of Protestant history is what holds back places like Italy, Spain, Portugal, and Latin America.