Astro Bob explains in more detail, remarking: "Jupiter with only one belt is almost like seeing Saturn when its rings are edge-on and invisible for a time -- it just doesn't look right." But, apparently, this is an event that happens rather more frequently than the Saturnian equinox, once every 3 to 15 years.
The photos above are from Anthony Wesley, the same guy who discovered the impact scar on Jupiter last year; but you don't need to be as fabulous an astrophotographer as Wesley to see this for yourself. You do, however, need to get up early; Star Walk (my iPhone astronomy app of choice) tells me Jupiter rises around 3:30 a.m. right now. If you don't feel like getting up early, just check out Wesley's website for more wonderful photos of Jupiter.