The Texas Live! Grand Opening celebration with take place on August 9-12, according to John Blake on Twitter. Blake says that there will be a free concert by the Toadies on August 9 at Arlington Backyard.
Texas Live! is a mixed-use facility by Globe Life Park and the Death Star, which will have a hotel, entertainment options, and the like. It is part of a deal Rangers ownership and the city of Arlington put together a couple of years ago, before the deal for the new ballpark was announced, and I suspect was a significant element of the Rangers and the City of Arlington agreeing to build the new Globe Life Field (which opens in 2020) and keep the Rangers in Arlington for the foreseeable future.
You can check out the Texas Live! website here.