Commercial open source software for BI has been coming up strong for the last years and keeps on marching forward at a rapid pace. For several years now, we have experienced in several projects that commercial open source BI is a viable alternative for the traditional vendors. Gartner has been slow to confirm that (as they usually are when it comes to open source), but they their recent market studies now include open source consistently. And today I noticed that also the proprietary vendors have to publicly admit that they feel the competition from the open source vendors. Look at this page on the MicroStrategy website. They clearly feel they need to compare themselves to Pentaho, and since they are comparing to version 3.6 which has been out for about a year, I'd guess they have been doing a lot of explaining to their customers since some time already.
