Tuesday's much-hyped wedding between Niles and Daphne on Frasier had NBC celebrating. The comedy attracted more than 21 million viewers, its biggest audience in nearly two years. John Ritter's 8 Simple Rules..., meanwhile, held up well in its second week with 12.8 million viewers — second only to CBS's season premiere of JAG (16 million). Finally, the season premieres of Smallville and The Gilmore Girls gave the WB its highest-rated Tuesday ever in adult demos.