It still may be, but it is taking a lot longer than anticipated.
Is it really? Most expected that the next round of expansion would happen around the time the TV deal for the Big-12 came up for renegotiation. The Big-12 losing a couple of members was a faux opportunity because at the same time they had all the wanna be applicants doing their song and dance routines, the Big-12 was cutting some back room deals to get an exception to the 12 team / 2 divisions rule for a conference championship. As soon as that deal was cut, expansion was DOA.