Denali doesn't have much for SSRS. I vaguely remember reading that the SSRS team got most of their big improvements in 2008R2 instead of lingering in Denali.
However, BIDS will be Visual Studio 2010. That alone is worth it.
In addition, Word and Excel export finally supports Office OpenXML file formats (.xlsx and .docx), which remove some restrictions from previous formats. The largest of these is counting rows and columns for Excel export.
Then the Project Crescent you mentioned: the Silverlight "Report" self-service tells the story. I'm not sure if this will really be part of SSRS; I'm not sure where it will fit.
I expect minor improvements to existing report objects, but I donβt think Denali will have much new for SSRS.
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