<p>Good question. The current ordering is actually #zoom/lat/lon (I accidentally reversed it in the initial description), which is the default for <a href="https://github.com/mlevans/leaflet-hash">leaflet-hash</a>. There's no real consensus or clear choice for lat/lon vs lon/lat -- Google, Bing, and Leaflet do it one way, GeoJSON, D3, iD, and other frameworks another.</p>
<p>Zoom will always be present in the hashes generated by OSM.org itself, so URLs that omit zoom would be coming from third-party source. What sorts of use cases do you think a zoomless URL would be used for? And when it is omitted, how should an appropriate default be determined?</p>
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