Everyone said Elena Liashenko was over, too. But last season was her best ever: she won two gold medals and a silver in the GP, and finished 4th at the GPF; then won silver at Europeans. She didn't do well at 2004 Worlds only because she'd had surgery for a cyst only a few weeks beforehand.
Kwan turns 24 next month, not exactly ancient. She is the reigning US Champion and bronze World medalist. She doesn't look done yet to me.