My LCD research is winding down. I found the Avnet Industrial LCD Solutions Guide to be informative. At 100 pages and 3.8MB, you'll want to save and view separately in stand-alone Adobe Reader. Great review of touchscreens, optical enhancements, and displays.
Avnet Industrial LCD Solutions 2006
Note that Page 37 starts the touchscreen section. Page 67 starts the industrial display solutions. On page 70, I was pleased to see a range of brightness values based on ambient sunlight values of 10K, 30K, and 80K NITS for transflective displays. Hopefully more manufactures will start to list this data as transflective devices become more established and more competitive in the market. An ECR listing would also be nice.