I've recorded tracks on my journey to and from work this week (logging the data using OziExplorer CE running on an IPAQ hx2490 with a Bluetooth connection to a BT-77 GPS receiver).

Last night I converted this from OziExplorer track format to GPX using GPSBabel, uploaded it into OSM and tried out JOSM.

I couldn't get josm_latest (downloaded that night, 16th October) to retrive any data from OSM (it gave an HTTP 403 error). I also had a josm_latest that I'd downloaded on 13th October and that worked.

Puzzled when I looked at what JOSM was displaying to see that there was a lot of mapping in my home town that I wasn't seeing on the slippy map. So, anyway, I added a short stretch of track that wasn't in the existing data and tagged it highway=residential.

This morning, it's on the map! Wonderful!

I've a suspicion that the other data I was seeing in JOSM isn't on the map because it hasn't got any useful highway= tagging.

Next step is to try adding tags to some of the existing data that doesn't display on the map to see if that makes it display.