I suspect that the packaging for ipods, etc. (and the materials to make them) is not greater than the materials for cds, LPs, etc. but I could be wrong.
I can't imagine we could get a complete data overview at this time but it would certainly be helpful.
There is no contest between, say, a CD digipack in a light wrap vs. virtually any hard plastic encased, plastic insert nestled iPod. Even the little ear buds are way overdone in terms of packaging. Then there's the retail floorspace now dedicated to the marketing of such things.
Now, as CD/DVD sales move online, more packaging is required and more transportation infrastructure and energy is used in the music retail industry equivalent of the single occupancy vehicle multiple trip model!