Gartner does a study where they evaluate companies based on "Magic Quadrants." Microsoft is currently positioned as a Leader in Gartner’s Magic Quadrants for Cloud Infrastructure as a Service, x86 Server Virtualization, Enterprise Application Platform as a Service and Public Cloud Storage Services. You can see an example here:
The leader quadrant contains company with vision and execution. This is where Microsoft has been placed in the following four quadrant based evaluations:
Public Cloud Storage Services
Microsoft offers integrated services with its Azure platform as the foundation. It also offers a variety of server products, including Office 365. Microsoft invests heavily in their infrastructure, although their pricing is often reactionary to Amazon's. They are highly stable in this market, and are seen as trustworthy. Further, their focus on performance and consistency in file services in collaborative environments is a strength.
However, some weaknesses include late engagement with IaaS, and limited partnerships with other vendors - which is hindrance in extending enterprise environments. Their biggest competitor is Amazon, which leads this category.
The quadrant above is for Public Cloud Storage. You can read more here.
x86 Server Virtualization Infrastructure
Microsoft has been developing Hyper-V and System Center VMM for six years, and they are becoming increasingly integrated with Azure. They have closed the gap with VMware in their infrastructure, however gaps in systems such as recovery remain.
Their biggest challenge in this space is marketing and a very strong customer in VMware, who has happy customers and great products. One of the points in Microsoft's favor is their price. Their business model does not depend on this sector, while VMware specializes on virtualizations software. Additionally, with open source software like OpenStack, being stuck as merely another proprietary solution is an ever-constant worry. Read more here.
Enterprise Application Platform as Service
Microsoft's Azure has evolved to support Iaas and PaaS, making these technologies much more approachable. Additionally, their cloud first mentality is paving the way to deliver more functionalities of the .NET infrastructure to Azure PaaS services.
Developers that are familiar with .NET are at home with Azure, and Azure's support of environments such as Python, PHP, Java, Node.js, etc, which enable developers of other backgrounds to join in easier also.
Their main competition is SalesForce, a more specialized company in this sector and the only one ranked higher than Microsoft, and some of the potential problems could be Microsoft's leadership regarding its core businesses. Read more here.
Cloud Application Platform as Service
Microsoft entered this sector with their Azure Infrastructure Services, bringing them into the cloud IaaS market. Microsoft's offers in this sector integrate and complement other services, such as Windows Server and Hyper-V.
This does offer problems, as the services are attractive to primarily .NET developers, especially as Microsoft does not offer many Linux options. Their main competition in this area is Amazon, which leads it. Additionally, their focus on making their software cloud first offers challenges to manage their infrastructure at a bigger scale. There will be a high reward if, or when, they succeed however. Read more here.
Not encapsulated by any one quadrant is Microsoft's Cloud OS. Their focus on this promises flexibility and a secure future for businesses. It has convinced companies to buy into their vision, with Aston Martin, United Airlines, and Telefonica being three Gartner customers that have.
Most blogs focus on Microsoft' consumer technology, hence it sometimes looks like Microsoft is playing catchup (or challenger, using Gartner's terminology) to other companies. Looking at their enterprise technologies, however, shows how dominant they are in many facets of the enterprise world. It is especially impressive that they lead all companies except one in each, and those are highly specialized in their respective fields.
Also, there is sometimes criticism on the lack of "vision" by Microsoft, when compared to companies like Google or Apple. However, one of Microsoft's biggest strength in enterprise seems to be their vision and understanding of their future and how their products work together.