I loved playing with Terraserver back in the day. However it was built to be a demo rather than a product. Their GIS products were Streets & Trips and then MapP

I loved playing with Terraserver back in the day. However it was built to be a demo rather than a product. Their GIS products were Streets & Trips and then MapPoint which then rolled into an online version that went through various MSN/Live/Bing rebrands. I don't think that Microsoft failed to realize how large a business mapping would become. I think the problem was mostly these products existed in the Ballmer era where Microsoft expanded into seemingly every niche without clear goals besides using up all the oxygen in the room.