Apple's original iPad has taken off to levels none of us anticipated when it was launched one year ago. Though it has very recently gotten some competition in the tablet space, the iPad still dominates the market and mindshare of new tablet buyers. After having sold 15 million units in nine months last year, Apple has now refined its design with the introduction of the iPad 2.

What, exactly, is new about the iPad 2 that differentiates it from the previous model? That's what we're here to tell you. We reviewed the 16GB WiFi-only iPad—same as the model we used for our original iPad review last year—and for aesthetic purposes, we chose black over white. (What can we say? We like a good visual screen pop.) So, on with the show.

Physical differences

The iPad 2, like its predecessor, has a 9.7" backlit multitouch display with a resolution of 1024 x 768 at 132 pixels per inch. There were earlier rumors that suggested the iPad 2 might get a higher-resolution, "retina" class display, but that got shot down numerous times before the iPad 2's launch. In the end, we ended up with the same resolution after all, which was not unexpected, but a little disappointing to some who had hoped for at least some kind of bridge between the old display and the iPhone 4's incredibly sharp graphics. It's more likely that Apple will increase the iPad's display resolution as part of the next major revision, which some believe will come later in 2011 (though a more conservative bet would be spring of 2012).

So, the display is largely the same as before. However, the glass protecting the display is 0.23mm thinner than the previous model, as discovered by iFixit as part of the iPad's traditional post-launch teardown. This is part of what contributes to the iPad 2's slight weight loss—down to 1.33 pounds from 1.5 pounds—but could also lead to easier breakage and damage to the LCD underneath. There have been some reports of "backlight bleeding" near the edges of the screen when watching dark video, but we didn't experience this problem on our iPad 2.

Speaking of weight, Apple touts the slight weight change as one of the iPad 2's benefits. We wouldn't describe it as imperceptible, but to us, it's not enough to write home about on its own. If anything, the weight difference plays into the iPad's redesigned casing, which is quite a bit thinner and smoother than the previous model (down to just 0.34" in thickness with edges that taper even thinner, compared to 0.5" of the original iPad).

Because of this, the iPad 2 feels much different and easier in the hand than the original—one Ars staffer described it as "Kindle-like"—making it also seem lighter. Still, it's not so light that it's comfortable to hold with one hand for extended periods of time. Just 1.33 pounds isn't normally a lot for one hand to handle, but the nature of the touchscreen means that you usually have to keep your thumbs off the screen and close to the edge when holding it, which makes the weight more noticeable.

The iPad 2 also now has a completely flat back, which is a bigger deal than it seems and a much appreciated change. Many original iPad users have expressed frustration at the device's ever-so-slightly rounded back casing, making it difficult to lay flat on a surface, but that problem is now (thankfully) in the past. And, as we mentioned during our initial hands-on with the iPad 2, the ports, buttons, and speaker are all now on the sloped part of the back metal casing, making them nearly invisible when looking at the device straight-on.

This design element doesn't affect audio coming out of the speaker grill much—even with Apple's smart cover flipped around to the back, which we'll get to later—but it does seem to make plugging things in slightly more difficult. The 30-pin connector isn't quite as easy to slide in as it once was, and the audio jack on the top is a bit more awkward. These aren't deal breakers, but they might be points of annoyance for perfectionists.

Oh, and how could we let a section about the physical differences slip by without mentioning the addition of a white model? Apple now offers each version of the iPad 2 in both black and white, which only applies to the front bezel and doesn't affect the color of the metal backing. As we mentioned earlier, we chose black, but the color is really a personal preference. We think the images on the display look better with the shiny black border versus a white one, so if you're looking for our advice on that front, we're sticking to black. But if you have a dire need to own white Apple devices, the white option at least looks nicer in person than it does in photos (in our opinion, anyway).