I was just looking around in SSH on my iPod Touch 2G Firmware 3.0 and i found the BlueTool init script for the iPod touch 3,1:
Found in: "/etc/bluetool/"
These references point to the use of the Broadcom BCM4329 chip...
The Broadcom BCM4329 integrates a complete IEEE 802.11 a/b/g/n system (MAC/baseband/radio) with Bluetooth® 2.1 + EDR (Enhanced Data Rate), and FM radio receiver and transmitter. By combining several proven wireless technologies onto a single silicon die, the BCM4329 enables mobile devices to support today's toughest media applications -- without impacting device size or battery life.