I miss it. But it's only you and me. Everyone else misses the throne room.
To paraphrase Sid Meier, the palace was there for extra goofiness and gameyness.
Just out of curiosity-
Do you, by chance, know where or when he said this?
Yeah, the video that dispelled any illusion I had about Sid:
http://www.youtube.com/watch?v=bY7aRJE-oOY
What I miss is not the palace itself, but the possibility to move the palace to another city making it capital.
That was Civ IV... yes, I liked that too... fixed capitals are rather a step backwards.
I know it really served no purpose, but I kind of miss the people loving me so much that they offer to add on to my palace and make it all awesome. I am a little sad that it has disappeared from the last few Civilization games.
I miss that, I miss the AI leaders changing their outfits with each Era (omg so much work for the art programmers lets make a crappy dlc instead), I miss wonder movies, victory movies and a replay.