>>Results on my Windows 7 Dell Latitude Machine
>>

>>CPU Manufacturer: GenuineIntel
>>CPU Name: Intel(R) Core(TM) i7 CPU       M 620  @ 2.67GHz
>>CPU Manufacturer: GenuineIntel
>>CPU Name: Intel(R) Core(TM) i7 CPU       M 620  @ 2.67GHz
>>Number of Physical Cores: 2
>>Number of Logical Processors: 4
>>HyperThreading is ENABLED
>>

>>
>>Did not know I had HyperThreading!
>
>Yep. Intel reintroduced HT into their processors with the Core i series.

HT was actually first present on some NetBurst Pentium 4s and associated Xeon processors. However, that implementation was poor, and Intel dropped it on the early Core processors. HT was re-introduced on some Nehalem and Sandy Bridge Core i processors.

My understanding is the current implementation is better than the NetBurst one, but still no great shakes. I've heard, on average, you get about 25% improvement in performance, so a 4 physical core/8 logical core Sandy Bridge would be the equivalent of about 5 physical cores.

http://www.hardwarecanucks.com/forum/hardware-canucks-reviews/39555-intel-sandy-bridge-core-i5-2500k-core-i7-2600k-processors-review-6.html