I read this article that some others have commented about. I have worked with Oracle on several major projects. In all of these projects, I have found 1 thing that Oracle does very well that Sql Server does not. If I want to do a genealogy, it is very easy with Oracle to do a genealogy and find the parents / children of an entry. It is not as easy to do this with Sql Server. This is very helpful in a manufacturing environment when you might want to find out all of the input materials for an output product that is defective. Given the fact that using Oracle within a MS environment has not been something that has caused headaches in the past, it is no wonder that MS is gaining marketshare. Add to this the problem of knowing how to properly tune Oracle and the pain that that intales, and Sql Server looks better and better.