I'm in Albuquerque, so haven't done much (bicycle) riding in Northern NM -- quite a lot of motorbike riding, however. That means I've stuck to the bigger roads (4, etc) but they're pretty incredible, with fantastic views.

Winters are cold but dry -- there's quite a bit of altitude, and quite a lot of elevation change. Certainly climbing territory. As mentioned, there is snow at high elevations and the accompanying skiing.