My WiFi access point (broadcaster) is not in the same box as my DSL router. I would recommend keeping them separate, as well as changing the broadcast name, password, the entire IP numbering or your network to something non-standard, limiting internet access to specific MAC addresses, etc. Make it dificult for the WiFi hunters.
An amazing number of people still go out and buy a Linksys WiFi DSL/Cable router, take it out of the box, hook it up and plug it in, and turn it on without changing any of the default settings. I have one or 2 in my neighborhood - if I knew who they were, I'd go tell them.
