I've replied in another thread with additional useful info: http://forums.arcgis.com/threads/80341-Issues-with-ArcGISTiledMapServiceLayer-in-IE8-and-IE7?p=28362...Regarding the specifics of the basemaps available, you can see what makes up each basemap by entering this in your browser's dev console:
dojo.toJson(esri.config.defaults.map.basemaps)
That will print out the default names and base map layers for each basemap option.Here it is, prettified:
{
"streets": {
"title": "Streets",
"baseMapLayers": [{
"url": "http://services.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer"
}
]
},
"satellite": {
"title": "Satellite",
"baseMapLayers": [{
"url": "http://services.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer"
}
]
},
"hybrid": {
"title": "Imagery with Labels",
"baseMapLayers": [{
"url": "http://services.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer"
}, {
"url": "http://services.arcgisonline.com/ArcGIS/rest/services/Reference/World_Boundaries_and_Places/MapServer",
"isReference": true
}
]
},
"topo": {
"title": "Topographic",
"baseMapLayers": [{
"url": "http://services.arcgisonline.com/ArcGIS/rest/services/World_Topo_Map/MapServer"
}
]
},
"gray": {
"title": "Light Gray Canvas",
"baseMapLayers": [{
"url": "http://services.arcgisonline.com/ArcGIS/rest/services/Canvas/World_Light_Gray_Base/MapServer"
}, {
"url": "http://services.arcgisonline.com/ArcGIS/rest/services/Canvas/World_Light_Gray_Reference/MapServer",
"isReference": true
}
]
},
"oceans": {
"title": "Oceans",
"baseMapLayers": [{
"url": "http://services.arcgisonline.com/ArcGIS/rest/services/Ocean_Basemap/MapServer"
}
]
},
"national-geographic": {
"title": "National Geographic",
"baseMapLayers": [{
"url": "http://services.arcgisonline.com/ArcGIS/rest/services/NatGeo_World_Map/MapServer"
}
]
},
"osm": {
"title": "OpenStreetMap",
"baseMapLayers": [{
"type": "OpenStreetMap"
}
]
}
}