Try out http://bl.ocks.org/snkashis/5666125 , and take a look at the console. Adding a circlemarker fires 'moveend' on the map in an infinite loop. This issue is present in 0.5.1 or 0.6-dev. Removing the `this.fire('moveend');` in https://github.com/Leaflet/Leaflet/blob/master/src/layer/vector/canvas/Path.Canvas.js#L56 fixes this up temporarily but obviously we need to dig a bit deeper here. Bisecting indicates we should be looking at https://github.com/Leaflet/Leaflet/commit/bd8d5ff71255cca4d5d58cde91e14d37addf0508