You know, I was thinking of posting something very similar, but you encapsulated my thoughts exactly. A fresh start would be quite fun. There was a ton of work that went into the old world, and I am sad that that may be lost, but I am quite excited about being able to build something new from scratch.

The biggest thing I was looking forward to with the map changes for 1.7 we were planning was the new exploration aspects, but getting to do it for the whole thing and getting to build new infrastructure with cool players is even more appealing to me.

Single player minecraft is only so fun for me. It loses some of its luster when there is no way anyone else will see what I am doing. I'd much rather play in a team environment where we can learn from each other and contribute to cool things.