You have to pick:

This is currently on the top 10 list, but I can't imagine why. In my mind there are two possibilities:

1) The content is just the sea floor lifted up. In that case it will be nearly useless land - salt encrusted rock. While this would be kinda cool, its not that great.

2) The continent is resource rich and/or arable. This will lead to a world war. The major players will all claim it and fight over it, and it will escalate to world war. No question.

So either this option is very slightly good, or quite bad. Certainly not top 10 worthy, in my opinion.

I definitely lack your confidence that new usable land would lead to a world war, or even a relatively minor war. There'd be a lot of _diplomatic_ tension, sure, but unless the island is encrusted with diamonds that taste like bacon I can't imagine what resources it would have that would be worth enough to fight a world war over.

The island continent is more immediately accessible and usable, but I think having a tiny second moon show up would give a tremendous boost to space exploration and development. IMO that's better in the long run.

Just think of when the americas were discovered. That led to all sorts of wars between European nations. There is already a cold war developing between China and US... this is sure to inflame that.

I wonder what an additional moon would do to the tides? Not to mention the female monthly cycle? Hmmm. Given the chances of twice as much menstruation and early onset menopause I am going with the new island.

It would have no impact on the menstrual cycle. There actually isn't a statistical correlation between the current Moon's lunar cycle and menstruation, so throwing a new one in isn't going to change anything.

I expect there'd be some tidal effects, but probably not very strong ones unless the asteroid was in an unreasonably close orbit (which probably wouldn't be stable, so that'd be ruled out by the terms of the WYR).