I don't think this is urging users to switch to Linux, but at least the huge penguin is the most obvious thing on the page: it's the biggest, it's visually dist

I don't think this is urging users to switch to Linux, but at least the huge penguin is the most obvious thing on the page: it's the biggest, it's visually distinctive, and it's smack in the middle of the page. So they are definitely trying to raise awareness of Steam for Linux to the larger audience. I just rebuilt my desktop yesterday, and downloaded Steam for it. The above is what you get when you click the "Install Steam" button on their homepage, and it definitely caught my eye.