Are we talking aesthetic philosophies, production philosophies, business philosophies, what?
Quite possibly all of the above, but the business end of things was always the chief source of influence on the other two areas. If you look at film history(specifically that of hollywood), it has gone through a series of 'ages.' You've got the Silent Era(pretty much self explanatory), The Golden Age(1920-1960's), New Hollywood(1960's-1980's), and The Blockbuster Era(1970's-present).
Each era marked a major change in the style of film making, how the studios did business, and how the films were produced. However, each change was largely the result of a change in how the bean counters wanted things run.
The bean counters decide what the directors and producers can do. Similarly this affects how the actual production is structured as far as the basic mechanics of making the film: location shooting vs. shooting on a set, how big a production crew you have, union contracts saying what staff like key grips and best boys and whatnot can do and what they can't do, and how much time is allotted for each stage of production, etc.
So, the Silent era was kind of a big mess, there were a lot of different small studios as well as the big ones, you had Edison acting like a mob boss trying to stop people from doing things he didn't like, you had vaudeville trying to compete with the films. This of course was because the whole business was brand new and noboby knew exactly how to do things right.
Then you've got the Golden Era which was highly structured. Films were churned out in an industrial fashion, directors and actors were often treated like indentured servants with multi-picture deals that they had little control over(bigger stars had more freedom, but often, many of them just had to go along with whatever the studios told them to do) writers were thoroughly limited in what they could put to paper, and the Hays Code was there too.
Finally in the 60's the Hays Code was abolished and a new batch of directors came on the scene, these guys used the freedom afforded them by the lack of strict censorship of the Hays Code to make increasingly explicit and graphic films using new artistic techniques. As the public ate up these new kinds of films which were a refreshing change from the formulaic stuff put out during the golden age, the studios decided that they should just give their directors carte blanche to make whatever they wanted. This worked fine up until the early '80s with a series of flops that culminated in
Heavens Gate and
One From the Heart which were unmitigated disasters.
Meanwhile, films like Jaws and Star Wars showed that a different kind of movie could be successful and the Blockbuster Era was born. The Blockbuster Era is marked by increasingly large budget films with a decrease in overall volume of films produced. There is more structure and restriction than you had during the New Era, but not anywhere near as much as during the Golden Era. It is more corporate and businesslike. Personally, I think we may be seeing the twilight of this era as Studios are being forced to shell out quarter billion dollar sums with only something like a 50-60% chance of making a decent profit. Meanwhile you've got rather low budget films that have a blockbuster feel to them like 300 or Skyline. These films rely much more heavily on visual effects and as a result cost only a fraction of what comparable films would. The beauty is that even a stinker like Skyline can make a profit with just an opening weekend gross of fifty or sixty million(which would be viewed as a disaster for films like Avengers or one of the Transformers films) because they only cost something like 20-30 million to make.
Anyway, the point is that IOTL, the different eras had a certain period of overlap, because it took a few years for the studios and bean counters to realize that the new model of film making was superior to the old one. So in a situation where you've got multiple different nexus' of film production with different philosophies operating simultaneously, it's more or less like having multiple different eras of film making happening at once, eventually there is going to be one model that comes across as superior to the others which will eventually whither and die. This will probably take decades, because by the point of the POD suggested, film making was still in its infancy and nobody knows what they are doing. So, I figure that maybe by the 50's or 60's you will probably wind up with the film industry centered around a single city as the industry there manages to outshine all the others.