Is there any ability to write applications for the new iPod Nano 6th Generation, if so where can I find more information on this topic ?
At the moment, no one is positive, but the evidence points to no. While the os looks like iOS, there are a couple interviews that indicate that it's a cutdown version of it that's not meant to run external apps.
That doesn't mean that couldn't change before launch or after launch with a software update though.