pivot table is probably the most interesting interface to BI cubes, I've hardly seen them used elsewhere!
so i can't really agree on your assumption that "other data sources" would represent 0.1%, in most business places i would say "other data sources" represent 100% of the usage
Free online tools to do pivot tables on spreadsheet data. Sounds like small business to me. People who already have their data in spreadsheets and don't want to hire a BI engineer to install SQL, Analysis Services, construct cubes, reports etc etc
so i can't really agree on your assumption that "other data sources" would represent 0.1%, in most business places i would say "other data sources" represent 100% of the usage