While I have surely the I3 series will beat down the X2's correspondingly whose checked idea was to keep back HT? If you desire HT you have to increase to the I5 650.

I3 Series Specifications :
530 - 2.93Ghz, 512K L2, 4M L3, 22X Multi - $138.00
540 - 3.06Ghz, 512K L2, 4M L3, 23X Multi - $143.00

I5 Series Specifications :
650 - 3.2Ghz, 3.46Ghz Turbo, 512K L2, 4M L3, 24X Multi, HT - $176.00
660 - 3.3Ghz, 3.6Ghz Turbo, 512K L2, 4M L3, 25X Multi, HT - $196.00
661 - similar as 660 except 900mhz GPU - 196.00
670 - 3.46Ghz, 3.73 Turbo, 512K L2, 4M L3, 26 Multi, HT - 284.00

I perceive them all hitting 4.5Ghz with good cooling and 5Ghz for the 660 and 670 models.