"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
Official Apple iPod Battery Replacements?
According to sources, Apple is planning on introducing an official iPod Battery Replacement program. Through the program, iPod owners will be able to send in their out of warranty iPods to replace worn batteries. The lack of an official battery replacement program has been a common criticism amongst iPod owners. Apple's official replacement service is expected to be priced at $99.
Replacement iPod batteries have been available from 3rd parties from $50 and up, but have only available for earlier iPod models.
Update: More details now available from Apple.