Yup, I've painted the upper cabinets white! I can hear the gasps from those who believe it's a sin to paint solid wood. I felt the same way once upon a time but I've learned that sometimes good design calls for the forbidden paint can.
In order to give the bulkhead the appearance of drywall, we applied Dynamic Dyna Patch over the seams, corners, and the grain in the wood. This stuff dries hard, doesn't shrink, and with a light sanding will be as smooth as ice. The plan is to paint the bulkhead the same color as the walls and the crown white like the cabinets. Getting there, five more cabinet doors to go! I cannot say enough about Zinsser Bulls Eye 1-2-3 Primer/Sealer. It seals the wood, blocks stains, and paint adheres to it like glue.