
In the meantime Google has enabled several other methods to create and publish your own map. One very easy way is to use Google Earth to map your points of interest, save them in a KML file, publish and link that KML file on Google Maps.
Here is my first try:
1) the raw KML file from Google Earth
2) the linked KML file on Google Maps
http://maps.google.com/maps?q=http://tour.regensburg.googlepages.com/regensburg_test.kml
Cheers, Matthias