Tagzania reports on the "Google Maps meridian bug":
It happens when you have markers at both sides of the 180 Meridian. That's roughly the day-change line over the Pacific Ocean, you know. For instance, this map covering some islands in the Pacific. It should show three markers, one in Fiji, west from the meridian, and two others east of it, at Wallis Island and Tonga, two Polynesian islands. Well, at first sight, only markers in one of the hemispheres show up. But scroll a little bit, dragging the map with your map, and the eastern points disappear, in favor of Fiji. (read entire blog post..)
This is bug has been acknowledged by the Google Maps team here.
This is an (embarrassing) bug, and we are working on it. I will keep you posted when it is fixed. Bret Taylor Product Manager, Google Maps