This has actually given me what seems like a really good idea. Whenever I cook my own popcorn I melt a bit of butter in the microwave (or use olive oil) to give it some flavor. For a while I tried to use margarine because for a while people thought it was healthier for you (even though a lot of the time it isn't) but eventually I realized that margarine has too much water in it. It would melt the popcorn and make it much less crispy.
If beurre noisette has less water content and it has a nicer flavor than normal butter, then perhaps making that as the popcorn flavor would make the popcorn tastier and more crispy.
I am going to try this as soon as I have a movie night. It sounds like it could really improve my popcorn.