While the couple played coy with the media throughout their romantic relationship, they were seen vacationing with one another in Mexico following the third season's November 2006 finale. She subsequently moved into his aforementioned pad last May.
Last month, rumors that Smirnoff and her current dancing partner had become romantically involved began surfacing and according to The New York Post, Mario Smirnoff and Mario had been spotted "making out by the valet with their hands all over each other" while attending the Mercedes-Benz Oscar viewing party at Los Angeles' Four Seasons hotel in February.
Smirnoff and Mario both subsequently stated they have a "professional relationship" and Lopez agreed, stating he had no qualms with his girlfriend dancing with the R&B star.
"I think he's doing a great job. I'm really proud of him," said Lopez earlier this month on American Idol host Ryan Seacrest's KIIS-FM radio show. "I've met him and hung out with him a few times. He's a great guy -- really respectful, really cool. I'm glad Karina got him as a partner."
Smirnoff was recently spotted with E! Entertainment personality Michael Yo, according to People, which reported the two were seen "dancing and canoodling" at a recent event at Hollywood's Beso eatery. Lopez is currently starring in A Chorus Line on Broadway.