We desoldered the EMI shield to see what was beneath...

It's an Atheros AR6002. Unlike the new iPod touch, this chip does not support 802.11n.

Atheros claims this chip is super power efficient: "The game-changing power efficiency delivered by the AR6002 significantly extends battery life. In fact, the AR6002 consumes 70% less power in active mode than competitive solutions and near-zero power in standby."