Psst, wanna buy a BI vendor?
If you consider the broad landscape, the industry has its "stack wars", with IBM, SAP (Netweaver), Oracle (Fusion) and Microsoft. IBM is, in my view, the best placed here since it is the only one of these that does not have application turf to defend (even Microsoft has its applications to worry about, and like errant teenagers to its parents, a big worry they are). IBM has planted its feet firmly in the master data management landscape, and to me it would seem entirely complementary and consistent for it to make a big play into the business intelligence world. Acquiring a company the scale of Cognos would certainly be the kind of bold step that would demonstrate that IBM is very serious about this area. It would firm up its "stack"offering in a quite natural way. Of course I am not privy to the internal musings of IBM, but this rumor makes more sense than many.