I own two, that I seldom wear, but obviously don't mind. Both T&A's (from back before I knew better), one blue with white collar and cuffs, and the other is a lavender gingham with white collar and cuffs.
I think that is a white high-collared shirt with a black ascot.
Yes, I realized that, but the cuffs are very interesting. They are yellow-striped which presumably matches the body. Of course, it's a high stiff collar, but still it's not something you see in today's contrast look.
Yes they are very 'in' right now. Everyone from A.P.C. to Gap is doing them. They are espcially popular in a gray/blue with a white color. I like the look a lot. Here is the post I wrote about it on my site (it's actually about the GAP Classics Redefined Campaign but I included Gap's contrast shirt under budget fashion)