Leyla Hadi of Gryffindor recently sent me some excellent rumors about books 5, 6, and 7.  Here they are:

There will be 7 books all together.
One of the characters becomes a teacher.
Harry has contact with Sirius Black.
Lupin and Pettigrew come back.
We will learn a lot about Lily Potter.
The Dursleys have financial problems.
We learn why Voldemort is bad.
The new Quidditch captain will be surprising.
We meet Bill and Charlie.
We find out Ron is worried about being poor.
Someone will die.
The books will be very scary.
Ron, Harry, and Hermione all fall in love with the wrong people.
Harry and Hermione
will not fall in love.
Ron and Hermione may fall in love!
We will find out why some witches and wizards become ghosts           and some don't.

Thanks Leyla!