"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
Official iPhone 6 and 6 Plus Cases Arriving Ahead of Friday's iPhone Launch
iLounge has shared some good photos of the brown leather iPhone 6 Plus case. The cases are very similar to the leather iPhone 5s cases with a microfiber interior to protect the iPhone itself, although the iPhone 6 and 6 Plus cases have an open bottom edge where as the iPhone 5s cases are enclosed with distinct holes for the various physical features.
At least one MacRumors reader has received his black leather case for the iPhone 6 Plus, while others are receiving iPhone 6 cases as well.
A Reddit poster has received one of each size of case, allowing for a comparison between the two sizes. The poster has also shared some photos showing how the two cases fit in the hand.
Apple's leather cases are priced at $45 for the iPhone 6 and $49 for the iPhone 6 Plus, while silicone cases are also available priced at $35 for the iPhone 6 and $39 for the iPhone 6 Plus. The leather cases are currently shipping with delays of a few business days, while silicone cases are listed as shipping in October.