Perhaps you've heard, but a little show called 90210 premiered last night on the CW (to record ratings ) and nobody is happier about it than lead actress Shenae Grimes, the smilingest girl who ever smiled. Though she's ostensibly playing the show's Brenda Walsh archetype, Grimes eschewed Shannen Doherty's near-goth hauteur to deliver two hours of the biggest, widest, most non-stop smiling since Denise Richards grinned her way through Starship Troopers . With the help of videographer Molly McAleer, we've assembled a montage of Grimes compulsively flashing those pearly whites; whether she's flirting with the school bad boy, bantering with a terrifyingly well-preserved Lori Loughlin, or wondering, "Gee, doesn't this high school seem like it came out of a generic Anytown, USA rather than a truly decadent Beverly Hills," Grimes simply can't stop beaming. Shenae, we're sorry — but like bad-girl blogger Silver, we're simply speaking the truth. Don't worry, we're still BFF's. Catch you at The Pit? [The CW ]