David Pogue of the New York Times lauds the new iPhone model as “substantially improved,” citing the improved speed provided by updated internals as making “a huge difference.”

With an increase to a 3-megapixel sensor in the new model’s camera over the 2 megapixels of the previous iPhones, pictures are better and Pogue states that “color and clarity are definitely improved, especially in low light.” Interestingly, the new feature auto-focus feature that allows you to tap on the are on which to focus has a substantial effect on the color and brightness of the resulting image.

Video capture works very well and earns praise from Pogue as “sharp” and “smooth.”

The voice command feature is the new iPhone’s “most useful change of all” in Pogue’s eyes, greatly minimizing the number of steps to place a call, as well as controlling iPod functions.

On the oleophobic coating on the screen to resist fingerprint marks, Pogue found it to work well to “keep the iPhone looking new longer.”
The last physical improvement over the iPhone 3G is battery capacity, yielding about 25% more power per charge.

Pogue also covers some of the new features in the latest 3.0 firmware just released today. In addition to the new audio recorder application, added Bluetooth profiles, universal search, and MMS, Pogue mentions the Find My iPhone feature available to MobileMe subscribers.

In the end, Pogue comes away from the iPhone 3G S pleased, claiming that it “doesn’t just catch up to its rivals – it vaults a year ahead of them.” These are telling words from a journalist who also reviewed the Palm Pre just a few short days ago.

Compared to David Pogue, Walt Mossberg of the Wall Street Journal is far less impressed with the iPhone 3G S, stating that it’s not as “compelling an upgrade for the average user” compared to the iPhone 3G model relative to the first-generation iPhone. He also goes on to say that the new iPhone and the 3.0 firmware “don’t deliver” since the iPhone does not have a physical keyboard, does not allow 3rd-party apps to run in the background, cannot show Flash elements on web pages, and is limited to AT&T in the U.S.

In agreement with Pogue, Mossberg notes that the increased speed of the iPhone 3G S is its most notable improvement. Though Apple has not provided details on the processor in the new iPhone 3G S, Mossberg says it is “50% faster than in the prior model” indicating that he knows a little more about its internals than Apple has released to the public.

Battery life was another area where the iPhone 3G S stood compared to its predecessor, even failing to show a low battery warning after intentional heavy usage. Unfortunately, the 3-megapixel camera didn’t strike Mossberg as a great improvement over the one in the iPhone 3G, nor can it come close to competing with higher-megapixel cameras in other smartphones, like the Nokie N97.

Mossberg’s bottom line is that the iPhone 3G S, combined with the 3.0 firmware, makes “a great product even better.” However, he notes that the new firmware has enough new features in it to dissuade people from upgrading to the new iPhone 3G S.

Andy Ihnatko of the Chicago Sun Times, an established technology writer who is new to the list of reviewers to get an iPhone model before its release, also weighs in on the iPhone 3G S. Its increased speed was highly noticeable from the start to Ihnatko, who noticed that “everything feels faster” and that the speed “enhances the entire user experience.”

Though you’d expect that faster speed would result in poorer battery life, Ihnatko notes that this is not the case at all, and while the change in battery capacity is noticeable, it’s not “dramatic.”

Ihnatko pegs the improved camera specs and video recording capability as the biggest new features, praising the auto-focus lens and macro focus capability. He goes so far to state that “other phones might have better lenses, but the iPhone 3G S might be one of the best cameraphones on the market” because of the ability to select the focus area in an image. He has posted sample photos taken with the iPhone 3G S in a Flickr feed here.

Ihnatko did not have as good as an experience with the voice control features, finding that commands are hard to carry out when the number of possible results are numerous, as is the case with a large contact list or music library. In particular, he experienced difficulty using voice command with his car’s connection kit designed for the iPhone 3G.
The digital compass is another feature that earned compliments, where Ihnatko found that its integration with the Google Maps application was “slick and impressive.”

Like Mossberg, Ihnatko notes at first the the iPhone 3G S is an upgrade that is a “more subtle decision” from the iPhone 3G. However, he found that after 10 days with it, he found upgrading “a tough deal to turn down.”

Other iPhone 3G S reviews: