A very interesting article about Americamisms and their flow into British English with examples. And of course with comments of the British like "Oh, God, how can one say like this! We all should speak proper English"=))))
http://www.bbc.co.uk/news/magazine-14201796 Actually I myself didn't find them annoying at all, sometimes even wondering "Is there really another way to say that?" But it was fun to read.
A story to the topic: I remember when at the camp "Dialog" I would always use the word "bathroom" (AmE) instead of "toilet" (BrE) - of course, my foreign friends would misunderstand me and ask "Why do you need to go to the shower now?". Yeah, all of them have never been to the USA... So I had to force my brain to switch to British English.
If you are gonna read the article, please, don't avoid the comments from the right! They are so to the point and really make a good explanation.