1. Nobody's going to read the page you redirected them to. They're just going to make a mental note never to visit your site again.
2. raw.github.com is not a CDN, and using it like one will result in poor performance for your site while wasting a lot of GitHub's resources.
Yeah, its tongue-in-cheek ... not to be taken seriously. More of a statement that people who're really unhappy about Opera could take action to promote an alternative.