difference between subway:station and railway:station ?

Hi all
I’m completly new to OSM world. I’m french, and It’s a shame to see the poor degree of mapping we’ve done. So I decided to take my bike and my GPS and to participe.

Today, I’m wondering about subway. I’ve seen on London and Bruxelles maps that a subway station is a {railway:station} node on a {railway:subway} way.
For a train railway, nodes are also {railway:station}. In this case, there is no difference between a train stop and a subway stop ? I think this could be very usefull to be able to have a disctinction between them.

So, I noticed that JOSM allows to tag nodes as {subway:station}. This particular tag isn’t listed in the map features on the wiki. Shouldn’t we use it to mark subways stations, design a icon for it (like http://www.flickr.com/photos/emiliojurado/2281616661/ for example) ?
We should so ba able to have :

  • {railway:rail} ways and {railway:station} for rails
  • {subway:rail} ways and {subway:station} for subway

Note that I’ve noticed that there is also a subway_entrance node tag for subway entrences (http://wiki.openstreetmap.org/index.php/Tag:railway%3Dsubway_entrance), but I’t really different from a subway station as a station can have many entrences; sometimes more than 200 meters away from the station.

Note that I’ve read that page : http://wiki.openstreetmap.org/index.php/Tag:railway%3Dstation

Maybe this topic should go to developpement forum ? I really don’t know.

Thanks
Bruno Duyé