After a week on the market, iPhone 4S continues to generate buzz.

Perhaps aided by the death of Steve Jobs, Apple's newest product has sold four million units in its first week, which is a record for the company's iPhone franchise.

Though iPhone 4S sales have exceeded expectations, it's not without some criticisms.

The blogosphere has been flooded with opinions, and they've been both positive and negative. The positives are that the camera's performance has lived up to the hype. Users have boasted that pictures taken in poor lighting come out looking great, particularly colors appearing more natural.

Video quality has been excellent, as well, due to its ability to shoot in 1080p, compared to 720p. This upgrade into full high definition distinguishes itself from iPhone 4, which is a more requirement for some loyal Apple consumers. The video camera has also shown a substantial upgrade in performance in bright light and darkness. If shooting video is your primary reason for buying a smartphone, this is probably the best product ever.

Some forums have claimed that there are issues with contrast clarity as there is a yellow tint. This complaint represents a small fragment of the consumers, but many Apple enthusiasts are good at making their voice heard on the Internet. For one user, the yellow tint turned out to be the fault of himself, not Apple.

I thought I had a lemon, so I went to exchange it, only to find out I enabled some handicap function for a blind user, said Ryan Reyes, of Los Angeles, who bought the iPhone 4S on Oct. 14, when it hit stores.

Overall, it's a good phone. It just needs some fine tuning, he added.

Then there's Siri, the voice-activated feature that talks back to you when you direct it to call people, it writes and reads a text message, and gets information. The signature feature on iPhone 4S, Siri has received the most attention in iPhone blogs.

The iPhone 4S poses the Shakespearean question: To use Siri, or to not use Siri? -- that is the question. To some, it's a lazy way to get information and communicate. To others, it's a welcomed relief from having to hit small buttons and is a time saver from having to write and rewrite things.

While many are infatuated with the feature, there are detractors who say that Siri doesn't understand them, and picks up outside noise levels too often. Siri will often tell you that it doesn't understand something when there is music in the background.

However, many people who have some gripes with Siri are the ones who continue to use it. So the feature is far more a positive than a negative for users.

Stephen Colbert had his fun with iPhone 4S and Siri to start his Tuesday show on The Colbert Report on Comedy Central.

Write the show, said Colbert, to Siri.

What would you like to search for? Siri asked.

I don't want to search for anything, replied Colbert. I want to write the show.

Searching the Web for 'Search for anything I want to write the show,' replied Siri.

What am I talking about tonight? asked Colbert.

No comment, replied Colbert.

Colbert ended his conversation with Siri by saying, F*** you.

I'd blush if I could, replied Siri.

So that's Siri in a nutshell via Colbert's playful wit.

As for other mild gripes, some have complained that the iPhone 4S has a 3.5-inch display, while, say, the HTC Titan has a 4.7-inch display. Again, it's not really much of a criticism as some people prefer a smaller phone.

There are also more petty criticisms of Apple's newest gadget. Many users wanted a different casing as they want to feel as though their phone is different from the iPhone 4.

When I have a new iPhone, I want to feel like it's new, said a former midtown Manhattan Apple Store employee who asked to not be identified. They should have differentiated the iPhone 4S more, so it never gets confused with the iPhone 4.