I bought some.
CPU-Z, Sandra, and PC Wizard all show the times as CAS 5.
BTW, I did benchmarks (sandra, superpi, 3DMark06, and PC Wizard) of 533 CAS4 vs 667 CAS5. I'll post the results later, but the results were very close.
Stay away from the G.Skill DDR2 667 CAS 4 on Newegg. They are only CAS 4 at 533 Mhz. At 667 they are CAS 5.
The specific memory I am referring to is: http://www.newegg.com/Product/Produc...82E16820231066