Normally when a tech company launches a product or feature that's billed as a potential "killer" of a popular incumbent, there's cause to be skeptical. Quite often, that's just unsubstantiated hype either on the part of the company itself or tech writers.

In the case of Spotify's new Web radio feature, we're not going to go so far as to say that it's a "Pandora killer," but its inclusion in Spotify's desktop client is going to give the up-and-coming streaming service a tangible advantage over the 11-year-old Web radio service.

Music recommendation engines can be a tricky nut to crack. Last.fm combines your listening history with that of many other people, and it does a pretty good job of relating songs and artists to one another. Pandora uses a more complex algorithm based on specific musical qualities such as tempo, tonality and even things as granular as the level of distortion applied to the lead guitar. The Echo Nest, which has a much bigger data set and powers dozens of music apps, uses an even more automated approach involving data-mining, acoustic analysis and machine learning.

The recommendations offered up by Spotify Radio are not quite as good as those on Last.fm or Pandora in many cases, but they're pretty solid and the feature has serious potential. We started stations based on a handful of artists across genres and time periods and found the results to be mostly appropriate without being too broad or overly obvious. We even tried a handful lesser known artists from a few decades ago and Spotify was able to rattle off sonically similar tracks.

The feature definitely has its limitations. For one, that stations based on an individual songs (rather than artists) seem limited. Those channels appear to operate as though you'd selected the artist, not the song. By contrast, when you put a specific track into Pandora, it looks for songs with similar aural qualities regardless of genre, time period or other broad characteristics. It does a pretty effective job of pairing up songs that actually sound similar. And if you don't agree, you can always hit the thumbs down button.

The experience certainly varies depending on what you enter. While many stations returned appropriate-sounding results, a station for the band Nirvana mostly brought up other well-known rock songs from the same era, including a slow, cheesy ballad by Aerosmith.

Spotify hasn't divulged what's fueling their recommendations, but it does feel pretty similar to results from The Echo Nest, which powers a number of music apps, including Clear Channel's Pandora cline, iHeartRadio. UPDATE: It is indeed the Echo Nest that's powering Spotify Radio, both companies have confirmed. The recommendation engine has some growing to do before it's a thoroughly viable alternative to Pandora. Still, the mere addition of such a feature to Spotify will make many users that much less prone to load up Pandora.

Spotify Radio is just the latest way users of the streaming service can discover new music. The company recently unveiled a platform for third party apps, included editorially curated selections from Pitchfork and Rolling Stone, as well as more automated recommendations from Last.fm. The app platform and the new radio feature will both be rolled out shortly to desktop users, but you can download a preview here.