Let me preface this question by saying I'm neither a database nor Azure expert.
It appears that MS charges by the size and number of Sql Azure dbases and not by the number of servers. Thus, cost-wise it seems feasible to put a single dbase on each server instance. My understanding is that sometimes it's more beneficial to put databases on separate, physical servers rather than on one machine in high use scenarios. Would/could the same be applied to Sql Azure virtual servers? Here's what I could find about Sql Azure server instances:
A SQL Azure server is a logical group of databases and acts as a central administrative point for multiple databases. Each SQL Azure server includes logins similar to those in instances of SQL Server on your premises." ([SQL Azure Provisioning Model](https://azure.microsoft.com/en-us/documentation/articles/virtual-machines-provision-sql-server/))
Let me also add that though all of the databases will be accessed and used by the same Web Roles, none of the databases will require data from each other, directly.
Sql Azure - separate servers?
Re: Sql Azure - separate servers?
The physical location of your database and the number of servers have absolutely nothing to do which each other. Wether you have 10 servers and 10 databases or 1 server and 10 databases, it is the same. In the end you will have 10 databases, located physically on various parts of the cloud in a distribution that you absolutely have no control over. They may be all 10 on the same physical host (unlikely), or each one on a separate host (much more likely), you won't be able to control nor will you be able to actually find out.