This gorgeous lady is a Rose-breasted Grosbeak. The males are a more accurate depiction of their species. The females have that fabulous lemony-goodness under the wing. Brave Roger is holding her to show you, knowing that that beak is heading right for his fingers.
When I first started banding, I had a list of "birds I would super-really-love to have in the nets to see." This species was one of them. However, when I offered to get the first one out, and was warmly encouraged, it became quite clear why. Those beaks rarely break the skin, but give you quite a good pinch if you are not careful. And since there is no obvious injury, it is really tough to get any kind of sympathy.