According to the latest build of the iPhone firmware 3.0, the next-gen iPhone - known as iPhone 3.1 in the documentation - will use Broadcom's BCM4329 chipset, bringing with it the potential of improved WiFi performance and radio functionality. The BCM4329 adds support for WiFi draft-n, together with power saving features and not just an FM receiver but a transmitter also.
The presence of an FM transmitter could mean that next-gen iPhone owners will be able to dump the third-party radio transmitters and stream music short-range directly to their car stereos. As for the improved WiFi functionality, as well as draft-n support the BCM4329 also includes compatibility with MIMO multi-antenna signal technology, 5GHz network support and channel bonding, which can couple two channels so as to boost throughput.
The existing iPhone 3G and iPod touch use the Broadcom BCM4325, which supports WiFi b/g and has an FM receiver. However Apple have locked down the latter so that it will only receive signals from the Nike+ exercise accessory. It remains to be seen whether the company will do the same with the FM capabilities of the newer Broadcom chipset in their newest smartphone.
[via iPhone Buzz]