Katy Perry on Grammys, Acting, and How Much Her Grandmother Loves Mario!

"My grandmother loves you so much!" exclaimed Perry. "You guys may not know it, but at the Grammys when I brought my grandmother, she's so in love with Mario she's like..." [touches Mario's dimples].

On her Grammy nominations, Perry said, "I'm very excited because they're nominating 'Firework,' which is really important to me. 'California Gurls' is great and 'Teenage Dream' is fun and nostalgic, but I feel like 'Firework' is doing something right."

Perry also revealed that hosting "SNL" was fun, but difficult. "You know what I really found out, surprisingly, this week on 'SNL'? That acting is really hard. It's not that easy."

Lopez mentioned that producer Harvey Weinstein was thinking of doing a Broadway adaptation of "My Week with Marilyn" -- and wanted Katy to play the lead. "Oh gosh! Broadway is very strenuous!" laughed the singer. "Obviously, I'm very flattered that he even knows my name and that he would want to do something with me in the future. But I think before I do anything, I need to take a little catnap -- a real long catnap, because I'm tired."