It turns out that not a lot of new stuff was shown during Sonic Boom 2013, but this Sonic Lost World cutscene was! Luckily for us, SegaFans on the internet captured it and now you can watch it on Youtube! This cutscene looks kind of promising, at least a lot better than anything from Sonic Unleashed or Sonic the Hedgehog 2006.
Sonic Lost World comes out for the Wii U on October 22nd, 2013 here in the States.
Thanks to Youtube channel TheRealSonicFan for the video!