With the brackets set and first round matchups set to tip off on Thursday, Nielsen has released its first annual Guide To March Madness, which tracks a range of consumer and media information surrounding the event.

“The NCAA Tournament is very attractive to sports marketers even in tough economic times,” said Tom Ziangas, SVP for Nielsen Sports. “The games playing out over several weeks make it a sort of mini-series for viewers. There’s always some unexpected drama or Cinderalla story – like Davidson College last year – that makes March Madness a compelling reality show as well as a prime sporting event.”

In 2008, the tournament reached nearly 100 million viewers in the US, with basketball hotbed Louisville, KY, delivering the highest ratings for a local market in the last five years.

Most Avg. Viewers, NCAA Championship Game (millions)

1979 – Mich St. vs. Ind. St. – 35.1
1992 – Duke vs. Michigan – 34.3
1993 – UNC vs. Michigan – 32.9
1994 – Arkansas vs Duke – 32.7
1983 – NC St. vs. Houston – 32.1

Top Local Market Rating, NCAA Tournament 5-year Avg.

Louisville – 19.0%
Raleigh-Durham – 13.0%
Memphis – 12.9%
Cincinnati – 12.9%
Columbus – 12.7%

March Madness On The Web

ESPN and Yahoo! were the two most-visited sports sites last March with 19.8 and 19.4 million unique users, respectively. Traffic on the CBS Sports web brand shot up 59 percent in March 2008 over the previous month. Online buzz spiked dramatically in March for last year’s Cinderella team, Davidson College. This year, there’s an additional mobile phone angle as CBS March Madness On-Demand is now available via an iPhone application as well as the desktop.

Download the Nielsen’s Guide To March Madness.