The posting specifies the job’s description as : “Testing and reporting hardware, software, and device driver bugs for Communications technologies including AirPort (802.11a/b/g/n), Bluetooth v2.0, gigabit Ethernet, and/or 3G Wireless WAN in a detailed, timely manner [emphasis added].”
Could this mean that Apple’s adding 3G to the MacBook line? Possibly, but it’s still precious little to base any sort of assumption on. For all we know, this could be in reference to testing that encompasses third-party 3G modems to check for interference with the MacBooks’ other built-in wireless systems. So don’t get too excited just yet.