I wrote about a similar topic here:
http://forum.brillkids.com/teaching-your-child-math/is-she-learning/msg32667/#msg32667I said:
Regarding the main question as to whether they are really learning, no one will know with 100% certainty. Personally, I feel that so long as they are looking at the screen, then the information is going in. In fact, some would argue that that is a more effective way of getting the information to go in, when you're looking at something but actually focused on something else - this is actually the right brain method!
See, right brain learning is where you by-pass the logical, critical, analytical left-brain so that the right brain can absorb massive amounts of info without the left-brain getting in the way. This is the reason why the flash method requires rapid flashing, so that you're not using your left brain to analyze (or count!) the dots, but using the right brain to take in the whole image and perceive the quantity. Similarly, there are other methods that try to disengage the left brain, like flashing patterns (which you focus on) while you listen to a piece of information (which contains the info you're trying to absorb).
So it could well be that your child focusing on the icons (but visually taking in the entire image) might make this more right brain learning than otherwise!