Self service BI is getting lot of attention, and there are lot of tools out there in the market from multiple vendors. Some with real great visualization and leveraging the new in-memory processing models. Remember that when it comes to Self-service BI you want to make it as easy as possible for the people in your organization to explore and mine the data. They shouldn't have to spend a lot of time learning new tools, new syntax, new ways to load data, instead work with familiar tools they are already aware of. This is where the strengths of Excel 2010 and the PowerPivot add-in (free) are, you can use the already great knowledge base of Excel within your organization and provide them with a faster and easier way to deal with large amounts of data from multiple sources.
I would recommend taking a look at the below case study from The Weather Channel who had gone down the route of selecting QlikView and back tracked that implementation and now have implemented PowerPivot.
Initially, The Weather Channel planned to implement QlikView as a BI tool. However, after experiencing scalability issues, the company decided to switch to a solution based on Microsoft BI tools including Power View, a new BI tool in Microsoft SQL Server 2012 Reporting Services. “We wanted to bring in data from multiple sources and add features that were either not possible or not easy to implement with QlikView,” says Drooker. “Another benefit of the Microsoft BI solution is that training is minimal. Why add complexity and increase costs with a third-party solution when we can use SQL Server 2012 and Power View to simplify integration with our existing technologies?”
Remember that for your self service BI solution to be truly self service you want to make it as easy as possible for the people in your organization that work with the data and derive insight.