I think that for the most part, the posts which receive higher reputation are those which tend to generate a lot of discussion. If a post catches someones interest and possibly causes them think then this post will undoubtedly generate XP. This could either be ++ or --.

Remember, voting is purely subjective and according to the individual's tastes. There are some guidelines out there but they give us a lot of room as well.

- all part of being part of a community. :-)

Mick