Can I trace data from Google Maps/Virtual Earth/Ordnance Survey/…?
No. Other sources must not be used as the base of any data uploaded to OSM. This is because their licences forbid you to do so. Only sources with compatible licenses – such as US Government information released into the public domain – may be used as base for adding OSM data. However, it is OK to use Yahoo! Aerial Imagery, as Yahoo! have agreed to allow OSM to use it. Better still, create the data yourself! See Potential Datasources for possible sources of data, with compatible licences, to use with OSM.
*Sadly, we had to bring back ads too. Hopefully more targeted.