Here's what I learned when I asked Jeeves:
I'll keep an eye on it for a few days, anyway. I wonder if the parents will come back and remove the eggs or just leave them.
"Basically, there is a good chance that the eggs have been abandoned, because they are infertile or are otherwise unable to hatch. There is nothing you can do in this situation. If the eggs were infertile, there were no baby robins inside, so no babies died."
Related Tags: American Robins, abandoned nest, eggs