While there are a lot of rumors floating around, there has yet to be any indication to anyone internally that WWE NXT will be going live or expanding to two hours. With that being said, if changes are going to be made, they are doing a good job keeping the news from leaking.
WWE NXT will tape TV this Thursday, and then again on September 11th and 12th, followed by October 12th. With the current TV taping schedule, an announcement on the changes would need to be made soon.