The game launcher opens links in IE rather than the user's selected default browser. This is probably intended behavior, because it uses IE for its display, but it's a bit primitive.

Steps to reproduce:

1: Install Firefox.
2: Set as default browser.
3: Profit!
4: Launch the LoL launcher.
5: Click one of the links (such as "Riot Games brings League of Legends to PAX")
6: The link will open in IE rather than in Firefox.

I second! Also, what if by some miracle, the user doesn't have IE installed on their system? I hear in Europe it's possible to get a Windows without IE. Or maybe they just removed it...