Try setting your router to Auto on the broadcast channel. Could be the channel it is broadcasting on is being drowned out by a near router that is on the same channel.
As it is seeing other networks I doubt the card is faulty in any way so going back to the store or Apple care center won't do you any good.
Make sure the router is set to Broadcast the SSID. Make sure there is NO MAC filtering setup on the router, WiFi or Ethernet ports. That is usually one setting on the router independant of wired or wireless.
Change the SSID and make sure you click the Apply button on the routers interface to complete the change of that setting (Leave password/key the same).
This is just to check. Make sure the router is set to hand out more IP addresses then you have computers connecting to it from either wireless or wired, DHCP setting.
Some of these suggestions are just a shot in the dark as even if some of those setting were enabled you should still see the SSID (that is IF it really is being broadcast.
What happens if you Wire the MBP to the router? Do you get an IP address and can you browse the internet?