I can see the feature already, and I'm not in the Beta program. Even on the free tier I could see and use it, but now I've "paid" for premium (30 days free for now...).
Anyway, I've actually used it twice for running, and here are a few thoughts...
- You set the tempo you want in 5 bpm increments, and Spotify will play songs that match it. That's how I prefer it, so I'm happy, but I find this increment quite coarse, especially considering that you cannot set the "tolerance"... I guess it is +/- 2.5 bpm, but it would be nice to be able to set it (under advanced settings if you willl).
- I have set "cross-fade songs" to OFF under settings, but in running they still cross-fade quite a lot. Again, it would be very useful to be able to set this to one's liking!
- This is the most annoying: I would expect the Running feature to work very much like the "radio stations", getting random songs based on some "starting point" (I particularly like starting a Radio from my "Liked from Radio" playlist), but pre-selecting the songs to be around the target BPM. For Radio, this works perfectly, and I do get quite random songs and artists everytime I start the same Radio.
However, for Running, the only "Radio" (or playlist as you call it) that my personal taste can have some influence is the "Recommended for You", and, at least for me, this playlist is stuck for some time after I started it on only two artists! It is very far from a random selection of artists and songs from my personal play history everytime I start it!
I hope you can make the "Running" playlists more like the Radios, but simply limiting the songs to a BPM range!!!
Leo.
PS: I just opened Spotify on my mobile now to check some stuff, and Running has disappeared!!! WTF???