The following wikipedia page says that 3d mode in bing maps was discontinued
http://en.wikipedia.org/wiki/Comparison_of_web_map_services
Whats the reason for that?
Is there any official announcement or page regarding this from Microsoft?
[GIS] Does Bing Maps have a 3D mode
bing-maps
Related Solutions
With Bing Maps API v6 it seems to be a bug that has not be update or investigated.
Though I note your not looking for alternatives but it would make sense to upgrade to Bing Maps v7 - Bing Maps v6 will be depreciated at some point in the future.
If you would be willing to update to V7 of Bing Maps API then you can use the GeoRSS support with SSL. using https://ecn.dev.virtualearth.net/mapcontrol/mapcontrol.ashx?v=7.0&s=1
http://rbrundritt.wordpress.com/2010/12/10/georss-support-for-bing-maps-v7-ajax-control/
QGIS don't use directly the layers of Bing Maps or Google Maps or Apple (forbidden, licensing issue) but use OpenLayers via Python (with the OpenLayer Plugin). This plugin allows you to add a number of image services (allowed) to your map canvas.
You can use them for your work, but if you want to publish the map, you will be bound by the terms of the licenses of Google, Bings, Apple, etc. .
Best Answer
It was abandoned in favor of "Bird's eye everywhere."