At the risk of being called a "jerk", here's another bump:
The Valkyria Chronicles 3 artbook came out today (Y3150 ~= $41), and Amazon dutifully delivered it right on time:
I only got to thumb through it for a few minutes, but it's pretty good. Basically more of the same, if you liked the first two artbooks -- though not quite as magically awesome as the first one, which came out of nowhere and felt like such a special treat to us fans. Better than the high-school-drama second, certainly.
You've got your artwork of all the characters, pre-release rough sketches, the original art that was scanned to make the game's background graphics (re-scan these for a Vita re-release, please!), character ideas that didn't make it (Margitte looks nothing like how she was first envisioned; Valerie has some reat-looking alternative hairstyles), and the obligatory swimsuit shots for certain female characters.
I haven't looked at the interviews yet. But so far it's recommended. If you're a VC fan and can get your hands on this book without too much trouble, get it.