Gotta be Kelsey Grammer!
It sounds like Darran Norris, the voice of Cosmo in The Fairly Oddparents, but I'm not 100% sure
Richard Thomas
The voiceover is done by English Actor and comedian, Jake Wood.
Sweeney MacArthur
Tom Ravenscroft.
Anthony Hopkins
steve belford
jeff bridges
i think it is ellen degeneris sp?
Jeff goldblum
Lance Henriksen (the "droid" from "Aliens")
I love that commercial, I like cats