At TechEd2008 at EILAT I was talking about SSAS2008 new feature.
Well, one of them is the aggregation manager which is EMBEDDED in the visual studio.
Those of you, who used it at the 2K5 version, had to download the N+BIDS HELPER from CODEPLEX and install it ... it was not so easy to install extension on the PRODUCTION machine, although it was quite good.
Well 2K8 has it inside, with much more new feature. Such us union the aggregation you manually made with the usage based optimization.
If you ask: "hey, what about remove duplicate?" well the application do a distinct query for you, so you don't have to worry about it.
Have Fun!
RONEN