Disco dust is probably what they used. It's available on the internet at cake supply vendors.
Holy crap that's a boatload of disco dust. That is not ok to eat. :(
Could be sparkling sugar and good lighting.
Oh yeah, definately disco dust - and a boatload of it, at that! Gross.
To clarify the person who said that's not OK to eat. Disco dust is plastic. I agree with Leah , you can find very pretty sparkling sugar colors and use a lot of it. I do not put disco dust on anything that someone will consume. Just because Elmers glue is non toxic does not mean I'll use it on a cake;)
Leah_s always has great answers. It COULD BE sparkling sugar and great lighting!!!
It's disco dust. You can just tell. In the parts of the picture that aren't blindingly reflective,you can you still see light bouncing off of...plastic.
No way that's sugar on those cupcakes.