I pegged the joints but left everything un-glued for maximum mobility with humidity changes. That is, after all, the whole purpose of going to the trouble of making this top anyway.
Planed smooth the oak pegs are nearly invisible - good looking joint. I'm really pleased with the lid - and it's heavy. Drop this on your hand and you're going to feel it.
I like the rough planed texture and much prefer it to a furniture quality planing job. The 1/16" crack at the joint bugs me, but not enough to spend any more time tightening it up. There are a lot of moving pieces at work there, and ground you gain on one end, it seems you lose on the other.