I think the growing number of requests from recruiting agencies for developers with OLAP/SSAS/Cube experience/knowledge may have a lot to do with how Microsoft (and others) are pushing this as part of their database "stack", even though 90% (tbh I think it's closer to 99%) of the companies who ask for this skill will never actually need OLAP databases. I could be wrong, but it does feel to me like it's a buzzword that doesn't really have a huge amount of practical use in most companies. I do a lot of SQL work and constantly get requests for SSAS from medium-tier companies in sectors like law, design, media, insurance.