"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
Space Black Milanese Loop Apple Watch Band Spotted on Apple Store
The Czech Republic Apple Store listing parrots much of the same information as the traditional Milanese Loop, pointing to a possible launch date in about a week. Besides a handful of new color options for the Sport Band lineup earlier in 2015, Apple has yet to expand its higher-end Apple Watch accessory market with as many options for customers.
The Space Black Milanese Loop's Czech Republic listing only mentions a 42mm option, although if made official it seems that Apple would also include a 38mm alternative, akin to that of the original Milanese Loop band. The new band was also spotted on the Portugal and Hungary Apple Store sites, but all of them lack any official buy button at the time of writing. As usual, today's spotting could be some kind of mix-up and there is a possibility that the Space Black Milanese Loop band won't make it to consumer markets.
Update: Links to the Space Black Milanese Loop's online store page have been removed, and now redirect to the existing stainless steel option.