Photo agency X17 certainly thinks he is. From their site:

Just who was the girl we spotted Nick Lachey with last night? After we spotted Nick leaving Sideways, we caught up with him at Teddy's with an unknown girl - and we do mean caught, as you can tell by our photos of the pair kissing in Nick's car and our video of them linking arms and walking into the club! But the topper? We stayed with him after he left Teddy's all the way to the Intercontinental Hotel - and saw him picking up Vanessa Minnillo! (Source)

Wow, ballsy move by Lachey. Not as ballsy as that time I went trick-or-treating in Harlem as a sexy Klan member, but ballsy nonetheless. Sure the internal bruises healed after a few months but the memories, they'll last a lifetime!