As a writer, I found my writing style changed when I lived in the States. It's not just the vocabulary and phrases that vary, there is also an energy and directness in the American vernacular that is quite infectious. They tend to be more economical with words, dropping prepositions when they are understood, and eliminating much of the padding you get in British spoken English. Every time I go back to the States I find myself reverting to a more American speaking style as it is just so much more efficient and punchy, and I enjoy the rhythms and cadence of it.