Following closely on the heels of new Napster and Rhapsody music service offerings, Yahoo! has unveiled Yahoo! Music Unlimited, an online music store with an all-you-can-download music rental plan (including loading songs onto select portable players). After fixing the main glitches in the public beta, it looks like Yahoo! has a winning service.

One of the big draws, at least initially, is the price. Buy a full year's subscription at the introductory offer (http://music.yahoo.com/unlimited) and you'll pay $59.88, which works out to $4.99 per month. By comparison, Rhapsody To Go is $13.32 per month with a year's subscription. Subscribing month-to-month costs $6.99, which is still much better than the $14.95 per month that Napster and Rhapsody charge. The company won't commit to how long this "introductory" offer will last, however.

To use YMU, you'll need to download the Yahoo! Music Engine, which provides access to the store as well as organizing, ripping, and burning tools. You'll also get Yahoo! Messenger, which is configured to launch automatically at startup. It ties in, since you can share music with friends who subscribe to the service.

YMU boasts a library of over one million tracks, which puts it on an equal footing with Napster, Rhapsody, and Apple's iTunes Music Store. We tested it against Napster by searching for the current top 20 albums on the Billboard chart, and found them roughly even (18 for YMU, 17 for Napster, including a few partial albums for both). But when we searched for the top 20 from Billboard's chart from 15 years ago, YMU was much stronger (14 for YMU, only 8 for Napster).

Yahoo! has benefited from its late start in the music market. By watching the others, it has learned how to create a simple and clear app that's full-featured yet easy to use. Artist and album pages contain links to bios, videos, and pictures, when available. These open in a browser window, unfortunately, instead of in the music-engine app itself. We love novel features like the ability to make an instant playlist based on any artist or to find fans of that artist and see what other bands they like. (This is similar to Musicmatch's AutoDJ, though YMU's approach is more convenient, since you can build a list directly from the album page). The playlist tool is not fast, often taking 15 seconds to load album information, but the interface is clearer than Napster's. Yahoo! has also built in its LaunchCast radio service. Subscribers get access to 150 commercial-free stations.

Downloads are all encoded as 192-Kbps WMA files, which is a higher quality than what most online stores give you. Streamed songs are 128 Kbps WMA, which is typical. The DRM scheme (and hence restrictions) for subscription content are the same as with Napster and Rhapsody: Songs will play only on the PC they reside on, or on the handful of certified Microsoft Plays-for-Sure devices; Yahoo! lists only nine compatible models currently—and no, the iPod isn't among them, of course. Purchased songs are 99 cents each (or only 79 cents for subscribers) and can be burned to CD or loaded onto any PC or player that can handle WMA files.

Yahoo! recently bought Musicmatch, and eventually YMU will be the surviving service. It's unclear whether the Musicmatch Jukebox applet will continue to be developed. YMU is actually pretty good as a jukebox, especially for a first version. It's well laid out and easy to use. It has most of the features of Musicmatch Jukebox, and higher-rate encoding to boot. YMU's engine lets you rip CDs from your collection into AAC, MP3, OGG, WAV, and FLAC formats. Oddly, you can't make WMAs to match the service's downloads; we hope this oversight will be addressed soon. For AAC and MP3 files, you can encode at up to 320 Kbps.

If you have a library of poorly or partially tagged songs, you'll love that YMU can tag them for you, thanks to a new built-in service from Gracenote. It runs automatically to fill in missing metadata, or you can right-click on a song to have it suggest the metadata it thinks is right. We found that it was useful, if a bit inconsistent; for some albums, it suggested all correct tags, but for others it missed nearly half the songs.

Still, the combination of high-quality downloads, great music catalog, and a rock-bottom price make YMU the music subscription service to beat right now.