Tart,
you will get differing opinions but...
IMO - they used to be a fantastic and efficient way of filtering and targetting traffic...
Now?
they are 99% circle jerks and have become a complete waste of bandwidth.
Some early toplists were very successful.. but then, as usual, every dik decided they wanted one as well.. thereby diluting the originals, and of course traffic to these became harder to get... so they started linking top 100s together and using blind link banners... leading to the BS mess that is toplists today.
Yet another way to jerk surfers aroud, make big counter numbers and lose sales.
There are still some legitimate toplists out there.. you just have to look hard to find them.
DD