Organizations could wait for the industry to settle on a set of standards that all collaboration vendors adhere to. However, this may never happen, and the delay prevents organizations from realizing the benefits of collaboration. Hence, the majority of organizations are opting for a single vendor solution.
Is there a viable alternative?
Wouldn’t it be great if there was a subscription service for collaboration features, where you could choose the application that you want (Cisco call control and video, Microsoft presence and Avaya contact center), just like with iTunes?
The idea of such a deployment model isn't exactly new, but where the iTunes analogy comes in is that Avaya, Cisco, etc. become the bands/artists generating the content, while the SaaS service providers play the role of Apple. Of course, everyone wants to play the role of Apple, and potentially the platform providers could go there—but wouldn't it be great if your SaaS provider operated as a middleware layer that let you choose from a menu of content (i.e., collaboration features) provided by multiple “artists” (i.e., Avaya, Cisco, Microsoft).
Middleware architectures are not uncommon in the world of IT applications. The IT applications strategy uses a common set of shared services for functions such as user authentication, directory services and others that can be standardized across applications. Organizations then choose multiple technology platforms that best meet their application strategy.
The middleware sits above the application platform layer and abstracts the application information that needs to be shared into a common middleware layer, which then makes these sharable across a variety of services. This obviates the need for developers to build home-grown application connectors or to have to replicate the same functionality multiple times between multiple applications and multiple services.

Client devices reside above the Middleware layer. Middleware also allows for numerous clients to access any information from any application silo.