Not to say that their argument is sufficient to abandon jQuery, but it looks like what they're offering is working directly with the DOM, instead of jQuery's wrapper. Again, I can't say I'm convinced, but at the same time, at some point, won't it be time to move to the native DOM? jQuery itself is abandoning support for old IEs, and once that happens (are they really going to still be supporting 1.9 in five years?) then the main reason to use jQuery, cross browser compatibility, will be gone, and it will be time to reassess what should be the standard JS standard library.
Edit: on the other hand, I feel like DOM traversal is becoming a smaller and smaller part of the JS I write. Maybe we'll find in five years that we don't need a DOM wrapper at all.