I went to a few different places in the forum and it appears I wasn't able to comment or vote. Is this a feature-- if it's because of Christmas, I find it an interesting and perhaps useful gesture. Otherwise, is this a bug (I'm using Chrome?).
Usually when the SE team does anything that affects the functionality of the site they will throw it into read only mode and a banner on top of the site will let you know that you cannot do anything but read. I haven't seen such such thing today and the fact that you could post this question contradicts this anyway.