Does ping come out with a new bag each year?

While that seems to be the case lately, that's a big departure from how they used to play it. The Hoofer and Hoofer 2 had a long run, and while the Hoofer 3 had a couple small detail changes (water bottle, colors), it was the Hoofer Xtreme that caused them to go through a bunch of revisions to the stand, top, straps, and build quality, eventually leading to the Vantage. I wouldn't expect to see a new bag from Ping until next year at the very earliest--not counting color changes.