I have the older Xenon jersey, and the new 2.0 offers a welcome round of improvements without compromising on the foundation of the kit: its superlative fit and air-channeling capabilities. Gone is the see-through mesh around the stomach, with more strategically (and modestly) placed ventilation around the shoulders and underarms. The jersey itself is constructed of a much lighter weight and better ventilated fabric, negating the need for overt ventilation panels. Gore also went with a full-length, locking zipper for quick and generous access to cooler air. There's nothing about the Xenon 2.0 kit to not like - and it's quickly becoming a renewed favorite in my rotation.
* I've always been a Medium with Gore, and the Xenon fits just as slim as expected