It was easy for him! Plus, he had no idea what else to say because his most recent Pop Idol had just kissed him on the cheek and was going to be spending time with him later like they were friends or something. That's a lot to internalize, as well as having to find something to say with his mouth? He's not that good of a multitasker to begin with...

"OK! I'll send you one! I'll see you later! have fun doing your stuff this afternoon!"

In a moment, he'd probably remember he hadn't even given her his name.