Pure numbers aren't the important thing here, IMO. How many college students are playing with DB2 or IMS on System Z? It's going to be a very low number, for a few very good reasons:<p><pre><code>  * while reliable, System Z is incredibly hard to work with as a programmer or sysadmin

  * in my experience, IBM flat out refuses to give any of their "serious" products to universities. They say "Oh, download DB2 Express-C" and that's the end of the discussion.
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If I know there are 1000x more people in the field with Oracle experience on common hardware than DB2 on System Z, I'm going to go with Oracle. Hardware is cheap. Good engineers/sysadmins aren't.