What the all have in common is they are each artist's best song by far! For me, 'Dirrty' wins it hands down. Controversial - check. Provocative - check. Overwhelming sex appeal - check. Production before its time - check. Christina's vocals - check. Semi-iconic (well not really but it's still amazing) video - check.
Dirrty is flawless as well, and it smashed WW so I don't want to see flopping comments. WCS is an anthem but it's a little early to compare it to these two.