Sony is showing off its new Walkman phone at CES. The W810 is quad-band, supporting the two major U.S. frequencies (850/1900) and the two international bands (900/1800). No carriers are signed up now, but Cingular and T-Mobile seem like the most likely takers.

The original W800i was the best all-around music phone last year, with a clean interface and relatively simple music synching. Although the W810 isn't a huge leap forward, if it can get the support of a major carrier it could make music phones a lot easier to get.