My current students speak a language peppered with words I never knew when I was their age. it's not that they're any smarter than I was; it's that these words simply weren't part of the English language. I'm talking about words such as: cell phone, emoticon, google (as a verb), unfriend (as a verb), playlist, iPod, spam (as a verb-- we all knew what that icky canned meat was), DVD, TiVo, internet, .com, techy, and wiki-anything. Back then, yahoo was simply another term for a country bumpkin and a net was something to catch butterflies with. Oh, and you definitely didn't associate a mouse with a computer.
I'm sure I'm missing many words. Feel free to add in the comments section any words you hear a lot now that didn't exist when you were a kid.