There are a number of portable devices scheduled for be released in 2013.
PengPod is wrapping up what looks to be a successful crowdfunding effort on indiegogo. They have a line of dual booting portable devices running GNU/Linux and Android/Linux. Vivaldi is another GNU/Linux tablet that has closed its pre-orders quoted from their site: “After an overwhelming response and thousands of pre-orders, the first shipments of Vivaldis have been spoken for.” Then you have Rasberry PI making a mini computer. Ubuntu is developing Ubuntu for Devices.
So is 2013 the Year of GNU/Linux tablets? Only time will, but it seems to have a good chance to grow and become more established in the tablet market.