DB2 10 is the most significant release IBM has shipped and this is reflected in its rapid adoption rate. Based on the number of customers I hear from who have either upgraded or say they're in the process of migrating to DB2 10, I can't think of another release that's been so quickly embraced. If you're ready to make the upgrade, you should know that IBM offers DB2 10 for z/OS migration planning workshops. Contact your local IBM team if you're interested in this type of training.
If there isn't a workshop in your area (or even if there is), check out the free IBM e-book, "DB2 10 for z/OS: The Smarter, Faster Way to Upgrade to DB2 10."
The first section of the e-book is authored by IBM distinguished engineer John Campbell, who takes you through planning for the upgrade. The second section is authored by IBM gold consultant Cristian Molaro, who highlights the potential cost savings that can be gained through upgrading to DB2 10.
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