The NCAA officially announced the four number one seeds, which we already knew, in advance of the full bracket release. They also released the sites those number one seeds will play at. There was speculation in the hours before the tournament that the NCAA Committee might make some more drastic measures, including moving Minnesota State out east, but that didn't come to pass.
Top overall seed Minnesota State will play in the Midwest Regional in South Bend. The number two overall seed North Dakota will be the West Regional in Fargo. They were locked in to this site as the hosts of the regional. Third overall seed Boston University will be playing in the Northeast Regional in Manchester, New Hampshire. Miami is the fourth overall seed and will play in the East Regional in Providence, Rhode Island.
This also confirms that the winner of the Midwest Regional will meet the winner of the East Regional in the Frozen Four, and the winners of the West/Northeast Regionals will meet in the other brackets.