European Union regulations require cell phone vendors to include micro USB connectors as a means of standardizing charging options for cell phones, a necessary move to cut down on the plethora of mutually incompatible charging options that have proliferated through the mobile phone industry. Rather than alter the iPhone itself, Apple has instead begun offering a micro USB adapter that connects via the existing 30-pin dock connector. Thus far it appears to be available only in the UK Apple Store, and at £8.00 it seems fairly inexpensive as far as Apple's accessories go. It will be available on October 14.
The adapter will allow you to sync and charge any iPhone (except the original 2007 model) via a micro USB cable connected to your computer, and you can charge your iPhone from a charger with a micro USB connection. This means you no longer have to rely on Apple's somewhat expensive dock cables if the one that comes with your iPhone breaks and you don't have a spare.
EU regulations do allow for Apple to offer the adapter instead of altering the iPhone itself, so Apple is now in full compliance with the standards.