CBS continued its strong May sweep perf Monday as “CSI: Miami” hit a new series high with an episode that introduced characters from upcoming spinoff “CSI: New York.”

The Eye net, a solid second for the month in both adults 18-49 and 25-54, easily won Monday in key ratings categories, also getting a boost from comedies “Everybody Loves Raymond” and “Two and a Half Men.”

CBS and NBC are the only nets to improve upon their year-ago May perf.

According to Nielsen, with nine nights left to be counted in the ratings period, NBC led in adults 18-49 with a 5.0 rating/14 share (up 14% in rating vs. a year ago), followed by CBS (4.0/11, up 5%), Fox (3.6/11, down 8%), ABC (2.9/8, down 9%), the WB (1.6/4, down 11%) and UPN (1.2/3, down 14%).

In total viewers, NBC (12.9 million) leads CBS (12.7 million), with the Eye expected to win the month.

On Monday, “CSI: Miami” (23.08 million viewers overall) achieved a series high in adults 18-49 (9.0/22), topping even its series premiere in September 2002 (8.6/21).

Show, featuring “CSI: New York” leads Gary Sinise and Melina Kanakaredes, beat the combined ABC-NBC competish by 8 shares in 18-49 and gave CBS its best perf in the hour since November 2001 (“Carol Burnett Show: Showstoppers”) and its best with regular series since the 1995-96 season (“Chicago Hope”).

In the preceding hour, both “Everybody Loves Raymond” (5.7/14 in 18-49, 16.07m) and “Two and a Half Men” (5.7/14 in 18-49, 15.20m) led their slots. “Men” is the season’s No. 1 new comedy in 18-49.

NBC tied Fox for second on the night in 18-49 behind a winning result at 8 for “Fear Factor” (5.1/15 in 18-49, 12.00m) and a strong silver-medal finish at 9 for the season finale of “Las Vegas” (5.2/13 in 18-49, 12.91m), the season’s No. 1 new drama in 18-49.

Fox was solid with an “American Idol” spec at 8 (4.2/12 in 18-49, 10.78m) and “The Swan” at 9 (4.4/11 in adults 18-49, 9.71m), while ABC didn’t have much to sing about with its spec “Motown 45” (2.9/8 in 18-49, 9.29m).

The WB did well with the season finale of “7th Heaven” (2.4/7 in 18-49, 6.86m), which put up its best numbers since November, but only so-so with the premiere of music reality skein “Superstar USA” (1.5/4 in 18-49, 3.46m).