Effect of number of extents on Oracle I/O performance

In Oracle 8 and 9 we saw that at 1000 extents performance began to drop off. At 2K extents it leapt, laughing maniacally off a cliff. I know that 10g is supposed to handle much more than that without a problem. Tens or hundreds of thousands perhaps? Does anyone have experience with just what the new threshold might be? Or is the architecture such now that it is no longer a consideration?

Thanks in Advance.

Joel Wittenmyer
Sr. Database Architect
Sr. Data Architect
HealthTrans

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