This morning I ran across a Wikipedia entry while reading Lessons Learned From Social Software Implementations by Mike Stopforth. In Wikipedia, Enterprise social software is defined as "social and networked modifications to company intranets and other classic software platforms used by large companies to organize their communication. In contrast to traditional enterprise software, which imposes structure prior to use, this generation of software tends to encourage use prior to providing structure." This is an interesting viewpoint, but probably too limiting to be useful.
First, "enterprise social software" is only part of this convergence of traditional enterprise software and the trends seen on the Web. Beyond social software, there are also the concepts of aggregation and attention that are critical to this new paradigm for enterprise software. On the Web today, it is becoming increasingly easy to aggregrate data from disparate sources to find the information you need. Most major Web sites and services support RSS. Many sites support custom "portal" functionality and preferences for news and alerts to enable users to define their experience. While search remains very important, aggregation and filtering of data is essentially bringing data to your attention rather than requiring that you search for it on your own.
The more formalized concept of attention data is being integrated into many applications. The Knowledge Network features of MOSS 2007 are a step towards attention data being integrated into Office and SharePoint. For instance, if you're working on a specific project you can be presented with relevant documents, people, and other resources that are related to that project. If you prefer communications and documents authored by your boss rather than your peers, you can be presented with that information first. If a certain business initiative in your company is more important to you than another based on your job role, your interests or your communications patterns, the data for that initiative will be more prevalent when you're interacting with applications supporting attention data.
These concepts have application in the enterprise and are clearly derived from and inspired by the current trends on the Web. And yet they're not "social software"- they don't promote social networking or focus on connections between people. In that sense, I think it is important to think beyond the scope of the MySpace phenomenon on the web when thinking about the next generation of enterprise software. Otherwise, many opportunities will be missed or dismissed as another "MySpace for my company" rather than a productive tool to help people better organize, find and use information.