Board Thread:Wiki Discussion/@comment-35301431-20131225235009/@comment-12633677-20140117040445

M does not stand for 100,000. For thousands of years now, M (not MM) has stood for 1,000,000, I'm sorry, but if you have to explain a category name, then it's not a good name, and we need to decide on something different.

I hate to put my foot down like this, but I think it's necessary. 100,000=100k, 1,000,000=1M, and 500,000=500k. Period.