In your review of the new iPhone 3GS, you said that AT&T had changed its upgrade policy so some buyers of the previous model could get the new-customer price earlier than planned. Can you explain this in more detail?

Almost all cellphones in the U.S. are subsidized by the carriers to bring down prices. Typically, existing customers—who have already benefited from a subsidy—can’t upgrade at the lower new-customer price (in this case $199) until they reach a point in their contracts where this subsidy has been recovered. These dates vary, based on a formula that takes into account things like the customer’s monthly spending rate.

When some early adopters of the 2008 iPhone model, the 3G, discovered they wouldn’t immediately qualify for this $199 “standard upgrade” price—the same as the new-customer price—they got angry. So AT&T made a concession, but only a partial one. It declared that any customer who had been told he or she couldn’t get the $199 price until sometime in July, August or September of 2009 would in fact now be able to qualify for that lower price starting on the first day of availability.

This concession doesn’t apply at all to owners of the original 2007 iPhone, or even every owner of the 2008 3G model. And it isn’t based on when you bought your 3G, but when the system told you that you could buy the new model at the “standard” upgrade price of $199. You can check the price AT&T or Apple will charge you for an upgrade by going to www.att.com/iPhone and clicking on “Check upgrade eligibility.”

I’ve recently heard that the new Palm Pre smart phone is unable to import data from the old Palm Desktop program. In other words, if you have Palm Desktop filled with data from a previous Palm model, you’ll be unable to get that data into your new Palm Pre. Is this true?

No. While the Pre isn’t designed to repeatedly sync with the old Palm Desktop software, Palm does offer a program, for Windows and Mac, that will perform a one-time import of your old data from Palm Desktop. It can also do a one-time import of data from certain other desktop programs as well, including Microsoft Outlook on Windows, and iCal and Address Book on the Mac. This program will help you move your data to one of the online services, such as Google, with which the Pre is designed to sync continuously. The software is called the Palm Data Transfer Assistant and is free at http://bit.ly/3lIaZ.

I am contemplating purchasing the 17” MacBook Pro rather than the 13” or 15” models because the antiglare matte screen is offered only with the 17”. How bad is the glare on the smaller screens and how cumbersome do you find the larger 17” MacBook Pro?

For a laptop of its size, the 17” MacBook Pro is remarkably thin and light. But I did find it cumbersome to use in coach seats on airplanes and to cram into small briefcases. As for the glossy screens, which are now the most common option on many laptops, they bothered me at first, but I don’t notice the glare now. However, both of these are personal issues. So my suggestion is to go to a store and see for yourself.

You can find Mossberg’s Mailbox, and my other columns, online for free at the All Things Digital Web site, http://walt.allthingsd.com.

Does the new Palm Pre smart phone use the traditional Palm operating system and the many programs that have been written for it?

Palm’s Pre, which is due out later this year to compete with the iPhone and the BlackBerry, doesn’t use this older software, which was once the best smart-phone operating system, but has grown stale. It uses an entirely new operating system called the Palm webOS, which will have to attract developers willing to write new programs for it. It is a clean break from Palm’s previous hardware and software.

How does the Clickfree computer backup system you covered last week compare with Apple’s Time Machine or online backup services like Mozy or Carbonite?

Clickfree simplifies the chore of backing up files to an external hard disk. However, as I noted in the review, it doesn’t back up your whole hard disk, it doesn’t work automatically in the background, and it doesn’t create a backup physically distant from your computer.

Time Machine, which is built into the Macintosh operating system, automatically backs up your entire computer in the background and includes a very easy method for recovering files. It works with external hard disks. But it doesn’t work on Windows PCs, and it doesn’t create a remote backup over the Internet.

Mozy and Carbonite are online backup solutions. Their advantages are that they work unattended and create offsite backups. But they aren’t intended to back up an entire computer, they don’t create a local backup, and they carry service fees.

Does my 13-inch MacBook come with the capability to view PowerPoint files?

No. While Macs come out of the box with the ability to view and create files in the Microsoft Word and Adobe PDF formats, they don’t come with a PowerPoint viewer. In order to view (and create) PowerPoint files on a Mac, your best bet is to buy the Macintosh version of Microsoft Office, which includes PowerPoint itself. There are other methods as well. For instance, Apple’s own lower-priced iWork suite can also open PowerPoint files and create files in the PowerPoint format. And some Web-based office programs, like Google Docs, allow you to view PowerPoint files on Macs.

You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.