Anyway, it wasn't the ~fun fact~ that caught people's attention: It was the fact that tens of thousands of people did not know Rachel McAdams played Regina George.
I guess a lot of people never put it together that she's the same person who starred in The Notebook.
Which, fair, because they are VERY different roles — and both films came out in 2004. (But she still looks the same, IMO.)
Nevertheless, people who saw both films assumed it was a different actress in each role.