Lots of exciting new computers today! And no matter what, we still get jazzed about processor speeds. But what's this Turbo Boost business Apple mentioned? Why do CPUs have two different speeds? It's actually pretty simple.
Turbo Boost makes your computer faster when it needs it...
As the name implies, Turbo Boost is... turbo. Let's say your new MacBook Pro has a 2.7GHz processor. It'll run at that speed until you try to run something that requires extra power.
...by overclocking your CPU...
If you need more power, your Ivy Bridge processor will give it to you by cranking itself up. Think of a jet hitting the afterburner. The fastest chips Apple are using can push themselves all the way to 3.7Ghz — a full gigahertz jump, on demand.
...without you needing to think
Great news! Overclocking isn't a pain in the arse anymore. Your CPU will figure out how many extra cycles it needs and then reconfigure itself. No need to restart, no need for trial and error — it's all handled by an algorithm Intel cooked up. You'll never even know it's happening.
...and saving energy.
With a processor that makes itself faster (or slower) based on need, you get more from your battery. Overclocking a processor has usually been a permanent affair. You boost your CPU for more speed, and it stays that way, running hotter and feeding hungrily on electricity the entire time. Turbo Boost only stays hot as long as it needs to. Smart!