When the Institute of Medicine was conducting its review of front of pack labeling systems prior to making its final recommendation to the FDA at the end of 2011, it addressed several existing systems that were currently in use.
Included in their analysis were NuVal and Guiding Stars. Both of these systems were deemed inadequate and misleading and the IOM ended with a recommendation that would be used across all products and would include a point earned for meeting certain criteria, only after an overall benchmark of "goodness" was achieved. My past posts in regard to this issue can be found here.
Unfortunately, the FDA is not ready to make the new national labeling system happen and I am most certain politics abound and work to delay the efforts.
You are probably seeing front of pack systems on the products you buy now, but education on their use has not begun and they are not the symbols created by health experts.
Some big grocers are themselves adopting the systems that the IOM discredited - which is really the fault of the FDA not the grocers. In the article I read today, a couple of the health experts are consulted and stand by the IOM report. You can read it here.