Microsoft has moved with impressive speed lately to bolster its credibility in the cloud. Microsoft is unique, its executives claim, in its capability to help customers use the same infrastructure software whether it they are running apps on-premise or in the cloud. Microsoft’s initiatives support hybrid cloud environments, where public and private clouds are tied together.

Microsoft has also signed a deal with Oracle that permits Microsoft to support the running of enterprise-popular Oracle apps, something that other infrastructure providers like VMware can’t do as seamlessly. While VMware can run Oracle on a VMware instance, Microsoft’s deal will allow Windows Azure to management the Oracle more efficiently.

Microsoft’s reach extends beyond the infrastructure layer: It offers its own platform as a service, Windows Azure. Indeed, in another move that will appeal to enterprise companies that are used to Java-based applications, Microsoft and Oracle are also working to bring Java support to Azure.

Microsoft also own SaaS apps that can run anywhere –- either hosted remotely and served from Microsoft servers, or running on top of public or private cloud infrastructures owned or managed by enterprise companies themselves. Office 365 comprises Microsoft’s popular Office suite – Word, Powerpoint, Excel, etc. – and Exchange Server for e-mail, Sharepoint for internal social networking, and Lync for communication and conferencing. Microsoft is also integrating things like Yammer for group collaboration, Skype for calls, and SkyDrive for storage.

In August, Microsoft also announced that it is adding PowerBI, a suite of business intelligence and data mining tools. This makes it easier for employees to do sophisticated analysis, helping companies avoid hiring and training data analysts to use things like Hive or MapReduce.

Microsoft is betting companies will want to buy software and infrastructure from a single vendor. There’s a significant cost to but and integrate software from up multiple vendors, according to Scott Guthrie, the corporate vice president of Microsoft’s developer division. “When things go wrong, who’s throat do you choke?” he told VentureBeat in an interview, referring to the frustrations that many companies have when their systems break down or run unreliably.

According to this argument, enterprise customers can call up Microsoft’s CIO office, and hold it responsible for fixing integration problems. “To have one mission support contract with Microsoft, it can simplify someone’s life, ” says Guthrie.

And if companies want to run popular third-party party apps like Workday, Salesforce, or Google Apps, they can do so on top of Microsoft’s Windows Azure cloud and get things like single sign-on functionality and security and identity management across all of these apps.

As such, Microsoft aims to lead a big trend: The move to a more “modular” stack, where companies simply plug and play public and private cloud app infrastructure as they like — depending on what they deem efficient, cost-effective and convenient.

On the other hand, Microsoft has a track record of being antagonistic to open source software, which is widely popular among IT executives, for being cost effective and offering code-level access. Microsoft’s challenge will be whether it can really continue to offer everything to all people and still satisfy them.

If you’ve used Microsoft’s cloud products, please let us know what you think, and get our free full report when it is released next month.