Tom seems like a nice guy. I have no idea why people think he's smug, he just comes across as very excited and bubbly to me.
He's definitely got rhythm as well, but for some reason I find I just don't enjoy watching him dance. He always seems a bit manic to me, as if he's overdoing it, and I find all the facial expressions, be they the quickstep persona or the paso persona, really off-putting. Admittedly the manic-ness could be Camilla's influence as I get the same feelings watching her dance, even when she's with Ian. I like them when they're interviewed on ITT, I just find their whole dance partnership a bit tedious, over-hyped and not particularly enjoyable to watch.
I'm in the minority amongst my friends though, most people I know love him.