Jeff over at Sushicam has a great post on reverse culture shock.
He is on holiday in America and has some startling observations:
Where are all the vending machines?
Were people in service type positions always this apathetic, or has Japan spoiled me?
[There are] Clothing stores where: A) the clothes fit me, and B) I can afford them.
I haven`t been able to get back to England since I`ve come here though I managed trips to Hong Kong and Shanghai. I could tell the difference in the quality of service. The change is something I`m looking forward too.

First thing I noticed last time I was back in London is just how big (fat) everyone, especially the women obv, were in comparison to here