Merriam-Webster has added about 100 new words to the 2007 version of the Merriam-Weber’s Collegiate Dictionary, 11th edition (which won’t be available in print until this fall.)
You can get a list of 20 of the new words at http://www.merriam-webster.com/info/newwords07.htm . I must admit that I hadn’t heard of many of these new words, but nocebo and hardscape are taking up residence in my vocabulary.
Just for giggles I took out three words and trended them on IceRocket. DVR, ginormous, and crunk. DVR won, as you might expect, though ginormous spiked huge around the time of the press release (wonder how many blog sites are reprinting press releases?)