I currently have a wifi modem/router that's about 5 years old and offers 802.11b/g. It's on the ground floor. There are rooms on the floor above that only receive a poor signal, which I'm trying to improve. I'm tempted in getting an AirPort Extreme but ... - It's significantly more expensive than seemingly similar other routers, and doesn't include a modem. Is this justified? - Is Apple likely to upgrade it soon? What significant features could the upgrade have? - Maybe I could extend the existing router's signal through a PowerLine wireless-N adapter. Would this work, however, with my current modem/router that's only b/g? Any recommendations or advice?