Yep, it's a different font. I've turned into a Segoe-tard recently. It also has a fallback to the Windows Phone version of Segoe, then Calibri, if it can't find either of those, then it just calls back to the standard sans-serif definition. Arial is so 90's.
The #vert-hoz stuff has been there ever since the "choose your destiny" page was put up. That's what centers the box vertically.
Oh! There are also a couple more changes. They are incredibly itty-bitty, but do a lot to prevent the page from coming up with scrollbars.