@jmalen123: Rodney Crowell's "Why Don''t We Talk About It" is from 2001. Lucinda Williams' incredible song "West" is from 2007, her song "Essence" from 2001. The latter, by the way, is the most intense song I've heard from this century, with a vocal performance absolutely lascivious, the lyrics full of wicked double entendre.
Johnny Cash's version of "Hurt" is from 2002, though he of course didn't write the song. He does however make the song his own. Was he too old to matter to you? 😉
But ya know, one element in a song's stature as a great one is how it holds up to the passage of time. Some songs improved with age, others become diminished (no musical pun intended). A lot of the late-60's music now sounds quite dated to me. Genius songwriters aren't necessarily born every day, or even every decade. Would you rather listen to great music from the 20th century, or mediocre music from the 21st? J.S. Bach was for many years considered too "old" for 19th and 20th century ears, but sounds far fresher to me than most music written in those two centuries. Perhaps my love of Bach explains my love of "God Only Knows".