Microsoft recently released a CTP of Power View on SSAS Multidimensional, (and yes, I know I’m a bit late writing about this, but I still wanted to give my two cents on it). So we’re edging closer towards the point where Power View and Excel will be able to cover all of your viewer needs (or at least most of them :)).
Years ago when I wrote about Report Builder on a cube and all the problems that that relationship created, I wondered when that would be fixed. Now that we have Power View, I’m glad that Microsoft is trying to make it a complete solution, adding layers to it gradually so that hopefully the end solution will be with as less “features” as possible. What I was most happy to read was that in Power View on SSAS multidimensional (aka DAXMD) the DAX queries are handled natively on the server and that the performance is good.
If you’d like to see the how the future of SSRS and SSAS looks like, I recommend you give the CTP a look. And if you’d like to try and influence the future development of SSAS Reporting please fill in the survey the SSAS team is conducting.