Along with Xiongguanlong, another new theropod was announced today in Proceedings B: A giant ornithomimosaur!
No, it's not the quasi-mythical giant-armed wonder, but it's still a pretty big ornithomime. Named Beishanlong grandis, is not only big, but fairly primitive as ornithomimes go. It's similar to Harpymimus, though without a skull, we can't tell whether or not it had teeth and to what extent. Clues from the post-cranial skeleton, however, place it in between Shenzhousaurus and Garudamimus. This is pretty interesting as it shows that ornithomimids evolved very large size at least three times (and depending on where Deinocheirus falls out, maybe four). Other large ornithomimes include Gallimimus bullatus from Mongolia, and Struthiomimus sedens from Canada. Beishanlong was larger than both of these, weighing in at 626 kg compared to 440 kg for Gallimimus. By my reckoning that makes it the largest ornithomimosaur known (except, of course, big D.).
Image here is from the FMNH press kit.