I'm in a similar situation--I've got a decent (if old) mountain bike, but am looking for something that would be better on the road (but still okay on dirt roads). I'm leaning toward a cyclocross frame, but with triple (mountain) gearing. The Bianchi Volpe seems like a nice possibility, though I'm leaning more toward either the Lemond Poprad or Gunnar Crosshairs frame, but built up to my specifications.