I was there on business though and that lowers the bar significantly on whether it is "worth" it. A lot of places are worth visiting if it's free.
If you enjoy eating raw, frozen fish; it's a must see! I'm not talking about sushi here. The fish is still frozen when you eat it. I was there in late Spring and the weather was really nice. (not being sarcastic, it was nice) The ice on the river was just starting to break up. It is very, very cold there in the Winter. It is Siberia after all. It apparently is very muggy in the Summer.
On the last night, the company I was visiting took us out to dinner at traditional restaurant. Besides the fish, we had horse and reindeer (both cooked and raw). Everyone else chased it with Vodka. I can only imagine that improves the experience.