Allowing photos and video clips to be attached to text messages, a.k.a. multimedia messaging (MMS), is standard on most phones these days. Yet, ironically, it’s been slow to come to the iPhone, despite the phone’s multimedia prowess.

Finally, AT&T, the exclusive carrier for iPhone, this week announced that that it would make good on its promise to offer MMS. It will be available by September 25 to owners of the iPhone 3G and 3G S.

Despite the promise, there are growing signs that the carrier’s data network may already be overstretched, suffering more than the usual network congestion. As the New York Times noted this week, AT&T is facing increasing ire from iPhone users, especially in certain cities, as networks slow as iPhone owners swell in numbers and employ a growing range of apps and functions.

Things are so tight that back in July, AT&T 3G data service went offline, leaving iPhone users stranded on the much slower 2G network. Apparently, the New York Times reports, the network slowdowns primarily affect users in large cities, where there is a higher concentration of iPhone users vying for the same resources.

There are rumors that iPhone may be coming to Verizon, a top-rated carrier that has a very strong and fast 3G network. But Verizon, too, may find iPhone too much of a data guzzler for its renowned 3G network. And it won’t be just iPhone. Other cell users have fallen hard for social networking apps like Facebook and Twitter, as well as other apps that reports stocks, weather, sports scores—which continuously draw on carrier data networks—can easily bring any carrier to its knees.

One ray of hope is the next-generation cell network called 4G, which provides a much fatter pipe for handling data, plus it’s many times faster to accommodate high-definition video streams, movie downloads, and other forms of network-choking entertainment. In theory, at least, it’s even fatter and faster than the broadband connections people have at home. But best estimates for practical 4G deployment is at least several years away. —Mike Gikas

Whether you’re attempting to listen to music or movies at home without disturbing others, or trying to hear the beat in noisier environments, a good set of headphones can come in handy. We’ve just completed our testing of several new headphone models, which range from portable insert-style earphones to over-the-ear headsets designed to be used at home. When you combine our evaluations of home and portable models with those that use active noise-canceling technology, there are now almost three-dozen tested models in our headphone Ratings (available to subscribers).

While you can easily spend more than $200 for a highly rated model, you don’t have to—we found several models with excellent or very good sound for less than $100, and a few for considerably less. The two least expensive recommended models in our Ratings cost only $20 each.

Our latest tests include not only new models from established brands, such as Bose, Grado, Koss, Sennheiser and Sony, but also some headphones from newer brands, such as Skullcandy, Ultimate Ears, and Monster. We also tested a new model from Auvio, RadioShack’s new headphone/cable brand.

Also, you might also notice that our headphone Ratings now include not just sound-quality scores, but descriptions of the overall sound. We hope this additional information is helpful when choosing between models that might have similar sound-quality scores, but different sound attributes (such as better bass response or a boosted midrange). Keep checking with our blog for other headphone news, including Ratings updates. —James K. Willcox