In my comp class today my professor made sure we knew that we as a generation have been changing the way our language is used. words we have used in everyday speech has mad it's way into what is to be our vocabulary.
check it out, words like bad, baddest, badder now have an entry to define them as "good", i just thought it was intriqueing
oh and this just made me laugh
http://dictionary.reference.com/search?q=fuck
edit* I also managed to find Fresh (to be) in the dictionary, as well as Smashed