Okay I made it to episode 31 without getting lost... But, if Light gave up the Death Note to the Shinigami it belong to and borrowed Misa's to resist losing his memories... Shouldn't he have lost his memories when Misa gave up the Death Note?!
Chances are ownership tranferred back to him sometime before she gave it up. And Mikami was just borrowing it, so Light didn't lose his memories.
Well, no, because Misa isn't Light. I'm assuming the Note's can be exchanged equivalently, in that it doesn't matter which note you have, you will still have your memory.
Um, no. He was using the real notebook for the most part. It was towards the end when Near had Gevanni tail him that he sent pages from the real note to Takada and used a fake. But If I'm correct, he kept the real note in a safety deposit box at the local bank.
