When I got out of new age and then saw Joel Osteen on TV, my first thought was "new age has infiltrated the church!!" I feel the same way about several other popular teachers.
I have nothing personally against this man. He seems like a really nice, likeable guy. It gives me no pleasure to say these things about him.
If you are looking for good, solid biblical counsel, stay away from him! J.O. is a perfect example of how a person can seem like a Christian, hold a bible in his hand, but yet preach new age "positivism" - not the gospel of Jesus Christ.