No, I’m sorry, a new iPhone software update hasn’t been released today. Nor will you find the highly anticipated, hotly rumored turn-by-turn navigation feature in the App Store. Consumer GPS giant TomTom has been promising such an app for months, but possibly due to legal complications with Apple’s notoriously stern App Store policies, their software has yet to surface.

Today, xGPS version 1.2 was released to jailbroken iPhones and iPod Touches- finally bringing turn-by-turn voice navigation functionality to Apple’s GPS enabled mobile platform. Navigation is based on top notch Google Maps data and the software has some pretty slick features like Night Mode and maps downloading for offline use, giving it a paid-app caliber polish.

It seems like developers are giving us an increasing number of compelling reasons to hack our iPhones, as more and more great apps are being rejected from the App Store and are becoming available in Cydia. My reason was for tethering- the ability to use my iPhone as a wireless laptop modem. And I suspect voice nav with xGPS will soon be the deciding reason for many others.

Jailbreaking might not be for the faint of heart, as it technically voids your device’s warranty. However, you might take comfort in knowing that you can always perform an iTunes Restore to erase all traces of the jailbreak hack.