JCKeeys,
Strange isn't it?
There seems to be a core set of songs that stand the test of time (for better or worse). There are also those songs that go in and out of favor (nostalgia era trends (50's, 60's, 70's etc), TV/movie songs, etc ). And then there are the prerequisite "current hits" (Backstreet Boys w/ vocalizer, etc) you are expected to perform, but my favorite songs are the ones that survive the test of time to become "classic" standards.

Scott