Chamberlain is saying that HomeKit compatibility is coming...but no products are currently supported. You could get the door opener now but in order for it to be opened/closed remotely, you need the Internet gateway which is purchased separately. Other users in this forum who are more knowledgeable on circuitry are stating that the current gateway doesn't have the required hardware to support HomeKit so it would require a new gateway. I have the currently-available gateway and it works flawlessly through the iOS app. But once they release a HomeKit version, you'll have to buy a totally new unit.
When Philips upgraded their Hue bridge for HomeKit, they offered current users a discount to upgrade to the new unit. I'm hoping Chamberlain does that here.