just wondering what the odds are that i got 2 maps that were exactly the same, playing about 4-5 weeks apart and with me playing as a different civ.
i played contenents on one (the 'quick start' option) with the English about 4-5 weeks ago on small and noble. then yeaterday i played custom continents as the chinese on small and monarch. both maps were exactly the same (i checked on worldbuilder)

This isn't really to do with luck, there's a bug that causes this. There's quite a long thread somewhere in the bug reports forum on the subject.

I wouldn't call it a bug, because it is a nature of "random seeding". The random seed is cranked out from a random number generator, which is NOT a random generator itself. This generator follows fixed rules to generate a seed, and the map is calculated from the seed. If you have the same input to the random number generator, you will get the same "random number".

It is like we ask you to think of a random number. Now, if I travel back in time and ask you the same question, everytime you will pick the same "random number". Or will you? That's a philosophical question then. ;)

There was a bug that caused people to get the same map over and over. The last patch fixed it though...