I think it's from Marsha, Lynne's white bantam cochin. My husband found it (I was so jealous, I've been checking multiple times a day for a couple months now), and he was so cute and eggcited and carrying it oh so carefully. My son took a pic and posted it on his facebook, then called his best buddies with the good news. It's so pretty and perfect.
Yes a pullet egg is from a bird that just started laying. They are smaller and usually rounder. They turn into "regular" eggs when they get to be a normal size and shape, usually in a few months.