I often wonder about the "theme" issue. I think it's very well organized here in the US. Maybe because being planning ahead is a typical way of life here.
I see it and feel like a complete outsider, especially when it comes to the point where people plan their own birthday or wedding celebration, decorate their kids' room or their kitchen or even the whole house - according to a "theme". Choose a theme and go for it! Be solid as a rock or act like one!
It can be a cute theme like Alice in Wonderland or a scary one like Star Wars, pirate theme, Caribbean theme or Asian theme.
Why do you have to be so focused when you're celebrating something or decorating your home?
Obviously and hopefully you won't experience just one state of mind or mood in this interior so why force it to be centered around A THEME ?
As for the cultural themes - Asian, Italian or Mexican themes are among the most popular - these must seem to the "thematologist" like a colorful way to combine your dream colorful vacation with a celebration of your birthday/wedding. You can stay at your hometown and experience all these lovely places - through napkins, costumes, food etc... That's so wonderful and so well priced too!
You can also bring these multi-million-movie themes to your own private space and then you can be part of a TV series or a big Hollywood movie and become with the famous, for a change! At least in your special day - and you know you deserve it.
And surely, there are all the pure, natural themes such as birds, cats, the coast, etc. that can make you feel more "green" and organic, one with Mother Earth, cleaner, nicer.
The school of life. To me it feels much like a horse who cannot see the sides and is forced to look only straight forward, like preparing homework for a very boring class.
Now we got the epidemics themes.
We had few years ago the "bird flu" the "crazy cow" and now we got the new one - "swine flu".
It is really a scary situation and hopefully all these top doctors and scientists will manage to handle this epidemic.
Dinosaurs, roosters, Barny etc... maybe I'm wrong (again) and it is good after all that people practice and are trained from early age to be focused first on themes for their private events... then they can get a theme ("Swine Flu," for example) and stay focused until they walk it in the right direction.