Technology moves quickly. Just a few weeks ago, we were anticipating an epic showdown between the 3rd gen iPad and Microsoft's Surface RT. Now, ahead of Surface's launch, Apple has already announced a brand new 4th-generation iPad. How does Microsoft's intriguing new tablet compare to the newly-refreshed iPad? Let's take a look …

Dimensions

The iPad 4 has the same dimensions as the iPad 3, so nothing has changed here. The Surface and iPad have identical thickness, but different length and width.

Surface is primarily a landscape tablet, as its display's oblong 16:9 aspect ratio may look odd in portrait mode.

Weight

These numbers are close, with Surface tipping the scales just a hair more than the 4th-gen iPad does.

Display

On paper, this is an enormous advantage for iPad. It has three times the pixels of Surface's display.

Surface, however, should fare better than these numbers would suggest. A renowned display expert says that Surface's ClearType display tech will make its resolution appear sharper than it is. It won't likely, however, be on par with the iPad's market-leading Retina Display.

Processor

This is the big upgrade for the iPad 4. Its A6X chip is a variation of the terrific A6 SoC found in the iPhone 5. Like the A6, it is a dual core processor, but the A6X has quad core graphics to help drive that Retina Display. Apple is advertising twice the speed and twice the graphical performance of the iPad 3, and early benchmarks concur.

Surface's Tegra 3 is still one of the better-performing mobile chips you can find, so it should handle most tasks well.

RAM

Benchmarks show that the iPad 4 retains the 1 GB of RAM found in the iPad 3. Surface RT, meanwhile, brings a full 2 GB to the table.

Storage

Microsoft has taken some grief for pricing Surface RT on even ground with the iPad, but the tablet does offer more storage. For the same US$500, the base model of Surface gives you twice the internal storage as the iPad does.

Wireless

Surface is, at least for now, a Wi-Fi only device. The iPad 4 is available in Wi-Fi only and Wi-Fi + 3G/LTE models. It also expands its Wi-Fi capabilities to cover dual-band (2.4 GHz and 5 GHz) 802.11n networks.

Apple also added new carriers for the 4th-gen iPad, including Sprint in the US.

Battery

The iPad has a higher-powered battery than Surface, but this spec won't directly translate into actual usage. Remember that the iPad's battery is powering a display with three times the pixels of Surface's. Uptimes could end up being similar.

Cameras

Apple updated the front-facing camera in the iPad 4, and Surface's cameras aren't likely to be in the same league. Microsoft is being vague about the megapixels in the tablet, only saying that they're capable of "720p video." This probably means that they're around 1 MP or less.

Intangibles

One of Surface's defining features is its add-on keyboard accessories. The Touch Cover, pictured above, is one of the most innovative mobile tech inventions of 2012: think of an iPad Smart Cover, only with touch-sensitive keys and trackpad. The only catch is that you'll have to throw down an extra US$100 (bundled) or $120 (separately) to add it to your Surface.

The iPad 4 ships with the new Lightning connector, which Apple is adding to all of its mobile devices. Its advantages are that it's tiny and reversible; its big disadvantage is that it makes your old Apple accessories obsolete. Though unauthorized vendors may soon offer cheaper solutions, Apple wants $30 for each Lightning adapter. Change is good, but it would have been nice to see the company eat some profit (if necessary) to acknowledge its customers' long-term loyalty.

You can't compare these two tablets without talking about software. The iPad runs the established iOS 6, with the world's biggest and best collection of tablet apps. Surface, meanwhile, is running the Windows RT branch of Windows 8. Since it won't run legacy Windows apps, its software is all tied to the Windows Store. This gives the iPad the overwhelming software advantage.

A bright spot of Surface's software, though, comes in Microsoft Office. The new RT version of the iconic productivity suite ships with the tablet for no additional cost. Depending on your priorities, this could be a big-time advantage, or a non-factor.

Summing up

If you ask Microsoft, Surface is less of an iPad rival and more of a brand new product. That may be, but countless holiday shoppers will compare the devices nonetheless. It remains to be seen whether Surface will be the market-changing product that Microsoft hopes it will be. At launch, all we know for sure is that it's a bold new device with an attractive design, innovative accessories, and a sparse software library.

The iPad, meanwhile, is still the overwhelming leader of the tablet market. This 4th-generation iPad is a minor update over the 3rd generation iPad, but its performance will see a nice boost. For a product that has thus far been untouchable, that may be all Apple needed to do.

For this holiday season's other big tablet showdown, you can check out our comparison of Nexus 10 vs. iPad.