64 teams in the NCAA tournament in 2000
Michigan State did not make the NCAA tournament in 1980 after winning the championship in 1979. Florida did not make the NCAA tournament in 2008 after winning the 2007 championship. North Carolina won the NCAA tournament in 2009 and will not make the tournament in 2010.
They were in this year's NCAA tournament. They made it to the round of 32 where they ended up losing to BYU.
The NCAA is in the middle of a 11 year $6 billion television rights deal with CBS for the NCAA tournament.
The first national basketball tournament was the National Invitational Tournament, the NIT. It preceded the start of the NCAA tourney. The first year of the NCAA Basketball Tournament was 1939.