Following tiles have the same tilenumber: level=9(for yahoo 10), x=341, y=154. You see mapnik, yandex, yahoo and bing.
Yandex tiles lay a little bit more to the north. The deviation depends on the zoomlevel.
For my program that can display different maps (also next to each other), because of this north shift, I have to adapt the code for converting lat,lon to tilenumbers and back. I need to know the relation between north shift and zoomlevel. Who tackled this before or has some info?