The first web site RIM loads is IFA.com. The PlayBook loads the entire site very quickly, well before the iPad does. Then RIM loads CBS.com. Again, the PlayBook bests the iPad in sheer load speed, and due to the Flash content on CBS.com, the web site looks much, much better on the PlayBook. The iPad displays a Flash Player warning, and stacks the content in what looks like a mobile rendering of CBS.com rather than the full HTML version.
RIM then conducts an Acid3 test for both browsers. They each score 100/100, but RIM points out that the iPad shows an HTML error.
RIM says that it cleared the cache and cookies for both devices, though it doesn't do this on screen. It also doesn't demonstrate with authority that both devices are indeed connected to the same Wi-Fi network and not a 3G network.
Other factors to consider: The iPad has a larger screen than the PlayBook, which takes more processing power to manage. We know the iPad has a 1GHz processor. The PlayBook has a dual-core 1GHz processor. Between the screen size advantage (if a smaller screen can actually be called an advantage) and the increased processor horsepower, the PlayBook has a leg-up on the iPad.
Last, the PlayBook, which has QNX under the hood, runs a user interface that is entirely based on Adobe's Flash and AIR platforms. Of course it's going to perform better than a device that doesn't have Flash at all.
Can we call this a definitive test? Hardly. But it's interesting nonetheless. Here it is for your own enjoyment: