Once a priest told me that Rowling, Harry Potter's author said in an interview that she studied the occult arts as a research to write the books. I did my own research on the subject and it confirmed what the priest said.
There's also the question of the plants that look like babies. I think that they show up around book number three. That seems to be related to abortion.
It is really a shame, because the books have a good side about friendship that I really liked.
Also, many people become interested in the occult arts after they read the books. Including children.
About Pokemon, I have played the original games when I was a kid. Maybe there are some strange elements, but the games seem silly enough. If there's anything evil about them, I think that it is much more related to a particular way to see the story than something that is intrinsical to the games themselves. They seem silly enough to me.
All in all, I could allow my kid to play Pokemon, but I would give Harry Potter for him to read.