This is a major item delaying B1G expansion. There's little reason for an ACC school to commit to the B1G until they see whether they can make more in the SEC. Clarifying exactly how the SEC Network will work and what rights it will have, is a precursor to being able to estimate revenue.
We may be about to see a bidding war between the B1G/Fox and SEC/ESPN for the top names in the ACC.
Then there will be state-level politics, eg if UNC has offers from both B1G and SEC and NC State offers from neither, can they arrange for UNC to pick one and pick up an offer for NC State from the loser? Same with UVa / Va Tech. That has the potential to hold things up significantly. The B1G's major bargaining chip here is it's claim to have academic standards -- that UNC and UVa are academically acceptable but Va Tech and NC State are not -- if this is credible and the SEC has no similar standards, then UVa/UNC to B1G and Va Tech/NC State to SEC is a plausible outcome.