Microsoft is slowly but surely plugging away at its Windows Azure cloud computing platform and indeed plans to release it by the end of the year, the company confirmed Tuesday.

More details on Azure, including pricing, should be available in the "coming weeks and months," Steven Martin, senior director of product management for Microsoft's developer platform, said in an interview. It's unclear when exactly pricing details are coming, but Microsoft plans to unveil new features of Azure later this month at its MIX Web developer conference.

Among those details, Microsoft will announce that it has added some relational database capabilities to SQL Data Services, according to a schedule of MIX sessions Microsoft posted online.
"The relational database is a technology with which a lot of people are familiar," Martin says. "People understand it and have skills around it. Making sure we have good portability of skills is something we're hearing. It's also an indication the kind of apps people are going to be trying to build are far more sophisticated than you might have thought."

The breadth of customer examples is still skimpy while Azure is in testing, but Microsoft is fleshing out the scenarios where developers and enterprises might use Azure. Microsoft announced a few of these examples last fall: Epicor is building an ERP system on Azure, Micro Focus built software that can run Cobol applications on Azure, and RFID startup S3Edge is building a goods-recall service that runs on Azure. An oil and gas company also is using Azure to move messages across a firewall that separates an AS/400 and a mainframe in different departments.

Martin said that, while today developers have to retool their on-premises applications to run on Windows Azure, Microsoft is moving toward a point where standard Windows Server apps will be able to run in the cloud. However, Azure apps can run on Windows Server today.

"What you can build in Azure can run locally now, but not vice versa quite yet," he said. Among the easier apps to move to Azure: Web services and .Net applications.

Microsoft won't disclose until later this year how many people have signed up for or are currently testing Azure, but for now, it's "issuing tokens for accounts on a daily basis."