There are a few experimental receivers such as
the ADS-B receiver on board ESA's Proba-V satelllite.
As ATCast mentions 1087.7-1092.3 MHz is simply the normal ADS-B band (1090 MHz band) already in use today. Prior to the agreement, this band was only "protected" for air-to-ground use. Now this band will be protected for space-based applications as well.
Iridium is planning to launch a completely new constellation of 66 satellites (called Iridium NEXT) to replace what they have today. This gives Iridium a unique opportunity to place an ADS-B receiver on board each of those satellites.
So they've formed a joint-venture (Aireon) with NAV CANADA to commercialize space-based ADS-B service. NAV CANADA will also be Aireon's first customer. Canada needs cost-effective ADS-B coverage within remote territories as well as the busy North Atlantic sector. Similarly, Ireland, Australia, etc., will also be early adopters.
The first Iridium NEXT launch was scheduled for last month, but that's now been postponed until April 2016 at the earliest. This delay may push Aireon's commercial service past the original target of 2018.
There are other providers also eager to provide space-based service. DLR and SES -- the European partners behind that Proba-V ADS-B experiment -- will likely propose their own solution.