MySQL and Oracle database have been supporting spatial capability for several years, now Microsoft SQL Server 2008 was also support it and joined OGC too. It seems that all vendor have strong interest into the Geospatial market. The upcoming Map 3D will also support SQL Server 2008. There's no extra charge and everyone can download free-of-charge express version. I have copied a sort of content from Microsoft as below:

Spatial data can be used in many ways, as the following list of examples demonstrates:

• A retailer Web site can display the locations of all stores as pins on a map, and find the nearest store to a given zip code.
• A sales manager can define geographic sales regions, and use them to match customers to sales representatives and perform analysis of sales performance.
• An architect can create plans for a new building, and overlay those plans onto a map of the proposed site.
• A driver can find the distance between two locations, and plan a route.
• A real estate agent can quickly identify properties that match a client’s requirements, such as houses over 20,000 square feet in size that are on the shore of Lake Washington.
• A mobile application can find all gas stations within 10 miles of a given location.

SQL Server 2008 provides support for geographical data through the inclusion of new spatial data types, which you can use to store and manipulate location-based information. The spatial support in SQL Server 2008 can help users to make better decisions through analysis of location data in scenarios such as:

• Consumer-focused location-based information
• Customer-base management and development
• Environmental-related data impact, analysis, and planning
• Financial and economic analysis in communities
• Government-based planning and development analysis
• Market segmentation and analysis
• Scientific research study design and analysis
• Real-estate development and analysis

More info

Latest Milestone Coincides with OSGeo Endorsement of FDO Technology