DB2 licensing summaries refreshed for PVU pricing
developerWorks article: DB2 and IBM's Processor Value Unit pricing
IBM is in the unenviable position of reworking their entire software licensing scheme to address the issues presented by various multi-core processors, so Paul Zikopoulos stepped up and wrote a developerWorks article to explain how these changes affect DB2 9. He also provides a bit of background on the factors that led up to this change. The good news is that dual-core processors from Intel and AMD get a bit of a break, since they count for the same number of PVUs as their single-core relatives.
At the moment, Passport Advantage still shows per-processor prices for DB2 add-ons such as pureXML, which leaves the potential buyer with the question of whether the feature is actually licensed by processor or by core. I look forward that issue being cleared up soon as well. UPDATE: The processor-based prices for DB2 9's add-on features have been replaced with PVU and user-based pricing.