I, 4 1, am gld 2 c da langwage chnge. Bout time itz brought up 2 date.
Ok, so I jest... But, having said that, as many have already said, language, dialects and usage is continually changing. Unless you are speaking/writing as your parents, grandparents and further descendants did, then I fail to see how you can take such umbrage at the evolution of language.
Language evolves based on the common influences of the time. In the same way Shakespeare (the most obvious of many) has influenced many of our phrases and spellings. American culture is a huge influence in this day and age, and therefore, the evolution of language has followed suit.
I have my own bugbears; the misplaced usage of direct instead of directly at times, for one. However, I think it's worth accepting that it's not so much that the American language is taking over and more that our language is evolving continually due to many differing influences. It will not be long before 'your' takes over for all contexts. 'you're' is a dying word it would seem.
If you can't beat 'em, join 'em is what I say. Right then, I'm off to have a cupcake...