MongoDB on Windows Azure provides two options for deploying the MongoDB database on Microsoft's cloud platform:
1) Windows Azure Virtual Machines allow more control over infrastructure but require more operational effort. Users can choose Windows or Linux and install software themselves.
2) Windows Azure Cloud Services decrease operational effort through automated management but provide less infrastructure control. Only Windows is supported and configurations are pre-defined.
Both options provide scalability and high availability through features like replication and sharding. Developers should evaluate the level of control and effort needed to determine the best deployment model for their application on the Windows Azure cloud.