How Big is Houston?

About six years ago I was in Phoenix visiting a friend when her dad casually mentioned that Phoenix was bigger than Houston. I kindly corrected him only to recieve a reply of disbelief.

Fast forward to this past weekend and I was spending time with this man's son, again in Phoenix. We were discussing Carmelo Anthony possibly being traded to the Houston Rockets. He was somewhat astonished that I'd think Carmelo would want to go to a smaller market than Denver. I had to kindly correct him as well.

So I am not sure if this perception that Houston is small is just from this family, Phoenix or even nation wide.

Have any of you run into this?

Wiki Link Showing Population Rankings