Interesting thread!
I took a look at that article, and one line stood out: "the amount of phosphoric acid in soda is minimal compared to that found in chicken or cheese. And no one's telling women to stop eating chicken."
So, I don't know that it's the phosphoric acid we should be worried about!
It's hard to tell what's going on with the osteoporosis link. There's a correlation between the two, but that doesn't mean the soda causes the problem. I thought the article did a good job of not claiming we know it's a causal connection. They also had lots of suggestions for ways to improve calcium intake if you do drink a lot of soda. So that's something people might want to consider.