Since then, most nights have been pretty similar. Some nights he's not ready for the book reading to be over, or for us to leave his room and will cry/whine/holler out for a few minutes in his bed until giving up and singing himself to sleep. At night, he stays in his bed, even when he's not happy about going to bed. I think because the room is so dark and he has his favorite stuffed animals with him, he feels comfortable staying put.
Napping in his new room and bed:
Naps have been a different story, a bit harder of a transition, but getting better and not terrible... The first few days were hard to get him to stay in his bed. With the room being lit up by day, I guess he felt more confident about leaving his bed. The first nap in his big boy room, we watched him through the video monitor climb out of his bed and walk around his room until he eventually fell asleep on a blanket on the floor. We waited until he was sound asleep and then moved him to his bed, where he took a decent nap. Since that first nap in his new room, he's learned to climb up to his bed to go to sleep once he's fiddled around his room a bit and the last week or so, he hasn't gotten out of his bed - so it's getting better, and thankfully still napping, ultimately.