One thing many leftist cultural critique folks ignore is the appeal of craftmanship (and craftwomanship) that make Hollywood movies and entertainment so appealing. Part of the advantage Hollywood has is the sheer dollars spent on US movies, which allows the employment of folks who can do a particular skill (make scene lighted just so, make shit blow up so cool, etc.). Some cultural critics like to think that an inspired auteur (maybe just like themselves) can replicate all those skills themselves on a tiny budget, but if one respects the specialized skills involved, that makes Hollywood's success a little more obvious.
And that success feeds itself since the geographical concentration of talent and the "industrial district" nature of shared talent development in Hollywood makes it tough for any other country to catch up, since talent will not move to a country for a few "blockbusters" made each year (as France attempts) but need employment year round for their specialized skills.
And then there is the reason that Hollywood can spend the money in the first place and expect to recoup its costs in sales. First, the US has a very large home market, something few countries producing films have (India is one other example, Cairo does well serving the general Middle East arabic speaking market). More importantly, and this is where the "cultural imperialism" debate comes in, movies that do well in that home market often do well overseas.
Besides the craftsmanship, the fact is that the US home market is diverse -- blockbusters in the US cannot appeal to just one niche cultural group and expect to do well. It is hardly surprising that goods made to appeal to US "mass culture" - in many ways not the assumption of a homogenized audience but in fact the expectation of its opposite in finding common denominators - do well in a global mass culture.
That lowest common denominator nature has its cultural downsides but its liberation from the narrowness of the specific in any one group is also real. While there is a reasonable fondness for the diverse specificity of different cultures, it is also true that that diversity in the abstract can be incredible oppression for those within that culture who are different or resist (note acid thrown on faces of women refusing the burka in Afghanistan as the extreme). The universal mass culture of Coke or US movies is a real cultural liberation for those in cultural opposition, however impoverished that opposition may be in substance.
Here is the conundrum-- homogenized non-diverse cultures can sustain their segmented robust slice of cultural expression, and diverse societies sustain mass culture, but can a global mass culture nurture robust sub-cultures not as tied to geography and repression as successors to those more traditional cultures? Not clear at all.
-- Nathan Newman