I applied only to UVA, and haven't heard anything regarding admissions yet. When I was emailing with UVA profs in early February last year though it sounded like they had made their admissions decisions in late January, thus I would expect the same timeline this year. Beyond UVA, I'm afraid I can't be too helpful to anyone in terms of insight into the decision timelines.
BTW, Mr Tea, a huge congrats on your U Michigan invitation! Very impressive!