It's painted tongue and groove paneling - available at any lumberyard.

Not just "any painted tongue and groove" planking. This is a higher grade that won't be found at the box stores. Only a lumber store will have a decent #2 pine quality 6" V-groove plank. Expect to pay about 1 buck per lineal foot and note that a 6" plank is 5.5" wide. Note this is not bead board as well. The finish is also not a brush-on latex from HD or Lowes. This is a cabinet grade finish and most likely a pre or post catalyzed lacquer in semi-gloss, applied with a HVLP sprayer. There was a lot of detail and craftsmanship in this ceiling, thus it looks Fantastic. It also could be a PVC plank, but I doubt it. Too expensive. This kitchen has a very soft appeal and if you can handle white, it's design is near perfect. Here's a link to professional finishes by Cambell: http://www.mlcampbell.com/products/categories/pigmented_topcoats