Originally posted by zerozero
In more technical terms, it operates similar to DDR memory, allowing data to be processed on both the raising and falling edge of your clock, processing 2X the data on the same clock pulse.
Not exactly. HyperThreading actually just makes much more efficient use of your processor by filling up empty execution slots that would normally go to waste. It does this by creating a second logical processor, so programs are basically 'tricked' into thinking you have dual processors. For a very in-depth article complete with diagrams, check out this page:
Btw mac_mogul, you should be happy to know that future generations of the Apple G5 processor will have HyperThreading capabilities as well