Yeah, it's interesting trying to figure out the logic on some of those.

It seems that the early seasons and B/A eps have good representation on the lower part of the list. The top half is almost all Spike/Spuffy/late season, though (Hell, I think Gone made it on there purely because of the naked!Spike scenes).

So while the early season fans were out in force, those mean ol' late season/Spuffy fans overpowered them! How horrible!