Hi Virginia! My sister recently did this in her kitchen and used actual wood bead board. It looks so beautiful! BUT, if you are uncertain about whether or not you will like it for the long haul, you could also use bead board wallpaper. It is affordable and so much easier to install. If you want to see my sister's kitchen you can visit our blog here:
What ever you use the bottom corner should be caulked...this is the most vulnerable area of a backsplash. with normal use a backsplash only sees occasional "splashes" and not a solid stream of water like in a shower.
The only time I have done this was for areas where water was not present. Id suggest PVC. A stained finish is beautiful.. but it certainly susceptible to damage over time.
i dearly wanted white beadboard backsplash. we found that heavy, embossed wall paper at Lowe's. we left it white for a long time but recently painted it grey. it looks like beadboard and no one will know unless they touch it. much easier to put up, and much more cost effective, too.
http://www.atthepicketfence.com/2011/12/blog...
Hope that helps! ~Vanessa