On Lists:

10) Lists are cool and easy to make and they are very useful.
9) They're entertaining much like the "rule of  3" used in music, speeches and joke telling.  
8) People have ten toes and fingers (usually) and there's something about that fact that has something to do with Top Ten lists. I just don't know how to fit it in.
7) I always learn something new when reading a Top Ten list.
6) I can usually find a reason to disagree with the list's number one item. I always think I know better than the person who wrote the list. It makes me feel superior and that's not a bad feeling.
5) Top Ten lists make you want to read them and find out what the list contains, so they work well when you want to draw attention to a blog, website, speech, etc. (see, it works, you're reading this list!)
4)  Top Ten lists can double as jokes.
3)  They can also double as a warning or as instructions or a packing list.
2)  If you can rattle off ten things that you'd put into a list, you have a fairly good idea about what you're talking about. So maybe it's worth reading the list.
1) Coming up with ten things to list in a Top Ten list proves that you can count to ten.