Evidence of Qualcomm baseband software has been found inside the source code of the current version of iTunes, confirming that Apple has ended its sole reliance on Infineon as the supplier of baseband chips for iOS devices. A decompile of the iTunes source done by an Italian coder uncovered two files that are telltales of Qualcomm baseband, though there's no hard evidence of which device they might be used for. Possibilities include the upcoming Verizon iPhone or a potential "dual-mode" GSM/CDMA iPhone 5 or iPad 2.
Piergiorgio "Zibri" Zambrini decompiled the iTunes 10.1.1 source code, finding references to two files - "partition.mbn" and "amss.mbn" ‚Äì which would be used for flashing a Qualcomm baseband chip, fusing it to a particular iOS device and carrier-locking it. The file "partition.mbn" is the flash partition table while "amss.mbn" is the baseband OS. Other files found in the decompile point to an Infineon baseband, either for backward compatibility of as an indication that Apple will use multiple suppliers on future devices. While there's no clear evidence either way, the inclusion of these files might indicate GSM/CDMA devices that could be used on virtually any carrier's network anywhere in the world.
Zambrini is well-known in the community, developing the ZiPhone one-click jailbreak/unlock tool for iPhone OS, which used an unsigned ramdisk to boot the exploit. He's since worked on jailbreaks for other devices like the Huawei E585 and E5830 portable MiFi 3G hotspots.