I must admit, I'm as entranced by the new Sony PlayStation Portable as the next guy. I've even acquired a bit of firsthand knowledge, as I was lucky enough to carry a Japanese version around for a week.

Yes, I do think it's going to redefine handheld gaming. But it's not going to be as popular or as successful as everyone claims. If Sony's expecting an iPod killer, this isn't it. Here's what I see as the good and the not-so-good in Sony's latest platform.

Screen: A standout display, for sure. It's big, wide, and captivating. Colors are rich and detailed. Response rates seemed superb while I was playing Ridge Racer. But there's a downside to all those pulsating pixels, too. First, Sony opted for a very reflective coating. This makes the image look great, but also turns the screen into a mirror in bright light. Even in lower light, the reflections can become annoying in some situations. Don't plan on taking it hiking; this is not a player for the great outdoors.

Graphics: Far better than the competition's, the graphics engine made the smallish screen look much bigger. Although some of the early titles probably won't take advantage of all the power, Ridge Racer at least looked fantastic.

Sound: I have no complaints here. The audio quality was simply stunning on my tests, especially when paired with high-quality headphones. The built in speakers are weak and tinny, as you can imagine, but the top-notch audio—when combined with the zippy screen—creates a truly immersive gaming experience on the go.

Controls: The PSP includes the standard complement of PlayStation 2 controls—although it has only one joystick and one pair of shoulder buttons—and pads that are reasonably easy to use. It has no touch screen, unlike the Nintendo DS, but includes a real portable-gaming breakthrough: a tiny round nub that appears to be the twisted progeny of a joystick and the IBM TrackPoint mouse replacement. Instead of having to be yanked back and forth, this "pointing pad" glides almost effortlessly across a small part of the PSP's surface. It provided a perfect stand-in for a steering wheel in Ridge Racer, and it'll probably become the controller of choice for all but the most precise and demanding tasks.

Games: The PSP's launch library is good for a new platform, with about two dozen titles available now. Over time, expect to see PS2 retreads and brand extensions galore. But those titles will only reinforce one of the PSP's problems: It's a portable version of a home console, but nothing more. The Nintendo DS, with a touch screen, microphone, and unique dual-screen design, offers more potential for breakthrough styles of portable gaming that don't rely on the archetypes established by console games.

Just because you build it, however, doesn't mean they'll come. Even though the DS has been out for four months, only a paltry number of titles are available, and few take much advantage of the unique DS features. The DS has one ace card: It's compatible with the huge library of Game Boy Advance titles too, which makes it a better upgrade for existing Nintendo handheld customers. Click — to get Jim's take on PSP movies, music, battery life, and more.