Britney Spears Lip Syncing in Las Vegas Shows – Is It Okay?

Britney Spears has kicked off her two-year residency in Las Vegas and while the show is receiving rave reviews, she is undoubtedly lip syncing. One website argues it's okay. Spears had initially said that all music would be performed live, but Planet Hollywood has already admitted that Spears sings to a backing track the entire show. The Huffington Post gives five reasons it's okay for Spears to be lip syncing for her residency at Las Vegas' Planet Hollywood Resort & Casino including dancing, costume changes and music only being one part of the show. Huh? Isn't music what Britney is known for?

What do you think about Spears lip syncing? Is it okay?