So what exactly is the Slacker Web Player? Put simply, it's a free Internet radio streaming service that allows you to create customized stations. But what distinguishes it from the plethora of other options out there (Pandora, Last.fm, and so on) is the fact that, down the road, it will be offered in a portable form via the Slacker Portable Player (and others eventually). That's right: a completely free music service that you can take to go.
Well, not completely free. In order to keep the experience gratis to the user, the Slacker Web Player will be ad-driven and will feature certain limitations. You'll be able to skip only six tracks per hour (the same goes for banning songs: you get six per hour). To do away with the ads and limitations, you can opt for Slacker's premium service, which is set to cost a very palatable $7.50 per month--half that of competitors, for those who are keeping score.
As for usability, even the most technically inept should be able to navigate the Slacker Web Player with ease. As the name suggests, the player is Web-hosted, and you can access it at www.slacker.com, where the majority of that page is dominated by a nicely shaded jukebox. The top section is a playback bar with play/pause and track-skip buttons, a volume slider, and Heart and Ban selectors, as well as various information about what's playing: album art, song and artist name, time elapsed and remaining indicators, station name, and the upcoming artist. Most of that is self-explanatory, but the Heart and Ban selectors warrant some illumination. These are both used to help personalize your stations. If you "heart" something, you make it a favorite, and it will (generally) come up more often. If you ban a track, it will never play on that station again.
In the left column below the playback bar, Slacker offers three buttons for switching between views. Now Playing shows you large album art of the current track, as well as the station name and what's played so far. If you click the album art, you can toggle between views: extra large album art, an artist bio, and an album review (if available). It seems like a minor feature, but the interactive experience is a nice touch. The next button down, Stations, shows a list of preprogrammed stations--mostly genre-based--as well as any custom stations you've created (check back soon for more info on custom stations). The Preset button takes you to a list of presets and offers simple instructions on how to save them.
Now for the in-between area: That little strip between the main view window and the playback bar. The two things of note here are the artist search box and the options dropdown. The former is self-explanatory: type in an artist you like to find their station on Slacker. Two of the major labels (Universal and Sony/BMG) and more than 100 indies are represented in the catalog, so you probably won't find everything you like at this time, but it's certainly a decent selection. The options dropdown offers various view modes (as mentioned earlier), access to account settings, and a selection called "stations", which is the most important for listening purposes, as it lets you further customize your stations. Go to Edit Station and you'll see a screen that shows you your banned and favorite songs and also an area that lets you fine-tune the station. You can adjust the popularity and time period of songs played, as well as select how often you want your favorites interspersed.
Of course, none of this does much good if the station programming is shoddy. Luckily, Slacker has real, live DJs selecting the songs, so the stations have been great to listen to so far. While I tended to like most of the tracks, I found myself questioning some of the artist stations. Rick James on a Lily Allen station? That seemed out of place to me. As did Eminem on the Ludacris station, if only slightly. They're both party rap, but it seems a Ludacris station should be more heavily weighted toward the Dirty South. Frankly, though, I'm taking the picky standpoint: I still liked the stations overall, and I'd rather hear variety over genre inclusion anyway. I think once Slacker gets some more labels, the programming will improve even more. Another minor complaint I have is that certain premade stations seem to disappear--there was a SXSW 2007 one that's no longer available, and that seems like a waste to me. Oh, and I wish there were more sub-genre stations so you could really dig down into preferences, but that is probably something that will improve over time.
As for the streaming performance, I experienced mixed results over a week of testing. Yesterday, for example, was flawless, with no pauses for buffering between tracks. Today, however, the stations refuse to play straight through: I actually have to skip to each next track, which is an immeasurable pain. But as Slacker is still in beta--and did I mention free?--we'll have to cut it some slack here. Audio is streamed at a variable bit rate in AACPlus v2, which sounds great to these ears, and significantly better than Yahoo's free radio streaming.