A typically intelligent and even-handed comparison of Oracle and Microsoft’s forthcoming OLAP offerings is available here from Mark Rittman (whose blog is also well worth a read). From a technical perspective I agree with everything he says, particularly about query language being a key differentiating feature. A little-known fact about Analysis Services is that you can query it using SQL, but it only supports a very basic dialect; it would have been interesting to see what the reaction of users would have been if AS’s SQL support was even slightly better than it is. Would it have affected the uptake of MDX? Possibly, since it might have discouraged users from investing the time and effort in learning the language which in turn would mean they never discovered the benefits it offers over SQL. On the other hand it would have been useful to have SQL-centric BI tools like Business Objects be able to query an AS cube natively; in the case of Business Objects, although their support for MDX and Analysis Services has actually been pretty strong I’ve always felt it’s somewhat peripheral, never properly integrated into their product line.