I am wondering if anyone knows of any (SharePoint 2010) COTS or OOTB ways of doing list aggregation/rollup that can be done separately from the Presentation layer?
Context: I have used a number of mechanisms to perform aggregation, and all of them mix the presentation and aggregation together. For example CQWP can query well, but you must then XSL or whatever to display; SP2010 calendars can do basic aggregation. I have used some 3rd party products, like CorasWorks, that can display things like Tasks lists and Calendars from multiple actual lists, but again the configuration of these ties the list/data aggregation to the presentation.
We have a number of 3rd party web parts to display list data in user pleasing ways. For example different ways of presenting Calendar/Time data in timelines and Gantt charts. Most of these can't do aggregation.
I would like to be able to create something that looks like a SharePoint list, that I can point these Presentation layer web parts at, but that is capable of collecting aggregate data. If I could make an 'aggregate list' look like a normal list then use the web parts to display I would be very happy (and so would the users!). At the moment I can either have the data presented in a way they like (and no aggregation), or have aggregation and limited presentation options. In some cases we have 'fixed' this by moving the data to a single list, but this is not always possible or appropriate.
I could code something up to solve specific needs, but would rather buy/get something that already solves this for me in a general purpose and reusable way. Does anyone know if such a product exists?