Are there any "rules" about igning POV in novel writing?

Having different POVs is good! It shows the reader what the reader needs to know. As for your main characters, cycling their POV is also a good idea, but don't stick strictly to that cycle. In some scenes, it might be better to have John, and in the next chapter, still John. Jill might see something the others didn't. Use your best judgment. If you want to talk more about writing, join a href="http://www.robotwrite.webs.com," rel="nofollow"http://www.robotwrite.webs.com,/a it's a new site that I came across.