Many PC users around the world will be trying Windows 7 for the first time on Thursday, but testers and other techies have been using it for months, or more. To give the uninitiated a sense for what to expect, we contacted five Windows experts this week and asked them to name two things: their favorite Windows 7 feature, and the area where they feel Windows 7 most falls short of its potential.

Reflecting the generally positive regard for Windows 7 among early users, some of the experts struggled with the second question but had no problem coming up with a favorite feature. In fact, in some cases, the biggest problem seemed to be narrowing it down to one favorite.

Some of the more high-profile new features are user interface tricks such as Aero Shake and Aero Peek, but the authors, bloggers and analysts we contacted pointed to many other areas not quite as obvious. Here's a summary of their responses.

Ed Bott, blogger and coauthor of Windows 7 Inside Out

Favorite feature: "My favorite Windows 7 feature is Media Center, hands-down. It’s our DVR and our jukebox, with an interface that is genuinely usable and slick. And it rates highly on the most crucial metric of all: Spousal Acceptance Factor."

Biggest shortcoming: "I’m disappointed that there isn’t a good migration/upgrade story for XP users. Yes, there are options, but none of them are particularly fun or attractive. I understand Microsoft’s reason for choosing not to offer an XP upgrade path, but it’s still difficult for upgraders." (Windows XP users can use a lower-priced upgrade version of Windows 7, but they have to make a clean install that involves backing up and later restoring data and programs. Windows Vista users can avoid that hassle with an "in-place" upgrade.)

William Stanek, author, Windows 7: The Definitive Guide

Favorite feature: "My favorite Windows 7 feature is not so much a single feature, rather it is a super-set of features called Windows Recovery Environment (aka Windows RE). Windows RE is a safety net that you can use to repair your computer if it fails to start. The single-best thing about Windows RE and the reason I’m such a big fan: a Windows RE partition with all the related tools is created and configured automatically as part of Windows 7 installation. This means every computer running Windows 7 has Windows RE."

Biggest shortcoming: "Asking me to name the biggest shortfall about my favorite release of the Windows desktop OS ever? Ouch, that’s tough and it’d be a let down, not a shortfall, and it’s this: another one of my favorite features is found only in the Professional and higher editions. The feature: Windows XP Mode. Another sticking point for me is that the some of my favorite Vista included-in-the-box applications are now available as download only. You have to get the apps from Windows Live now and they’re very different from the originals."

Michael Cherry, analyst, Directions on Microsoft:

Michael Cherry

Favorite feature: The ability to run Windows 7 on low-priced netbook computers. "I am now running Windows 7 Professional Edition on a netbook with only 1GB of RAM, and I love its performance. ... If they can improve the performance profile at that end, then I'm going to love it even more on my Dell with a 64-bit processor and 4GB of RAM."

Biggest shortcoming: "I still don't like all of these versions, the different versions," Cherry said. "Too many, and too (difficult) to draw a line between them." He cited the example of BitLocker, a corporate data encryption system available in Windows 7 Enterprise Edition but not in Windows 7 Professional. A better approach, he said, would be for Microsoft to offer one low-priced version that can be configured for different "roles," as the company does with Windows Server, installing only the features needed by a particular type of user.

Paul Thurrott, Windows SuperSite; coauthor, Windows 7 Secrets

Favorite feature: "There's no one, major new feature -- it's a bunch of little things, it seems. I guess if pressed, I would probably go with the taskbar, and the features that come off of that, like the customizability and the Jump Lists, which are essentially per-application Start menus, which I think is really exciting and interesting."

Biggest shortcoming: None in particular. "You have to look at it in light of the previous release, because this is an update of Vista. This in many ways is correcting that problem. This is a refinement of what came before, not a brand-new thing. For that reason, they've already covered the bases I think with all of the big complaints last time around."

Woody Leonhard, Windows guru; contributing editor to Windows Secrets

Woody Leonhard

Favorite feature: HomeGroup. "It makes sharing among Windows 7 computers very easy," Leonhard said.

Biggest shortcoming: Difficult to pinpoint one. Setting up television and some other media isn't as easy as it could be, and there are too many versions of the operating system. "But other than that, Windows 7 is great," he said. "It really is the best version of Windows ever. I think they've finally hit a home run."

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