Both shows are seen as the hottest rivals for best dramatic series, though there is also stiff competition in the offing from such old and new favorites as Boston Legal, Heroes and House.
The Emmys will air live on FOX from the Shrine Auditorium in Los Angeles at 8 p.m. ET (tape-delayed on the West Coast).
After the Emmys, Entertainment Tonight and PEOPLE will host the stars at their 11th annual post-show bash, this year headlined by Duran Duran. The gathering will be held inside L.A.'s Walt Disney Concert Hall.
And the Nominees Are ...
Besides its best dramatic series nomination, Grey's also racked up supporting acting nods for four of its stars – T.R. Knight, Sandra Oh, Chandra Wilson and Katherine Heigl – while The Sopranos ended its series run with 15 nominations in all, including two for stars James Gandolfini and Edie Falco.
In the race for outstanding comedy series, the nominees are Entourage, The Office, 30 Rock, Two and a Half Men and Ugly Betty, which is the show TV columnists are predicting will be the one to beat on Sunday – as is its star, America Ferrera.
The overall top nominee going into the ceremony is HBO's made-for-TV movie Bury My Heart at Wounded Knee, with 17. (See the complete list at Emmys.org.)
Seacrest's Gotta Dance
Earlier this week, Emmy host Seacrest – who not only is emceeing the ceremony but is officiating on the red carpet for E! TV – told the Hollywood Reporter that the Shrine ceremony will kick off with a musical number that he "may or may not be" a part of, depending on just "how confident I feel on the 16th."
When asked about it by Extra on Friday, the American Idol host, 32, added: "That's so obvious, singing and dancing, so I'll probably attempt to do that. There's a very interesting costume change, which could be the biggest mistake of my career ... it's that embarrassing."
Seacrest also promised, "I'm going to try and make the show fun ... and I'm going to try to have a sense of humor about it, and I hope the people watching have a sense of humor, too."