First u should know that laptops are designed to handle very specific voltage and thermal loads, overclocking ur laptop WILL void your warranty, and if you dont kill it outright in the first few months of overclocking, you surely decrease its lifespan considerably. Just b/c a desktop can be safely overclocked, and really overclocked with the right knowledge, cooling and parts, in NO WAY translates to laptop overclocking. Especially if your not an experienced overclocker there is almost a certainty you will fry your laptop pretty quickly. As such laptop bioses rarley if ever allow for settings to overclock, so you need a hacked bios, which are not easy to come by and especially harder on a boutique laptop like an AW. Theree isnt really a market for upgradeable cooling solutions (fams/heatsinls/water/peltier/etc) for laptops. In the end usually only the uber of the uber geek go for laptop overclocking as it is such a risking proposition with very little payoff.
You only get 2 bennefits from overclocking a laptop, a marginial increase in speed/ game framerates, even if you gain 7 fps in WOW from 76 to 81, you woulnt be able to notice it any, even 15 to 20 isnt much help, and secondly u get a larger e-penis........but I digress.
If you want to start into the world of overclocking, get a desktop too, and OC the hell out of that, as desktops are mix and match, those parts are designed for a higher variation of operational conditions....cough overclocking cough....
Now there is one caveat, certain power notebook providers like hmmm AW do offer/have the ability to overclock vid cards from in OS utilites, but u still run into the same issues, increased chance of hardware failure of the grfx card or other components, runs hotter, parts/laptop have a shorter lifetime, less battery life, and all that to shave off a minute of a 45 minute video encode or pick up 3fps in Crysis.