This isn't an issue on Spotify. You can't heart/star a podcast in the same way you can add music to your library. Podcasts have a separate library tab. The playback interface actually changes as well, instead of shuffle/repeat you have skip forward/back 10 seconds like an audio book.

I have premium, so one gotcha maybe whether you can download podcasts for free? I would be annoyed if I had to sit through both Spotify's ads and the product placement in podcasts. (does Spotify insert inline ads into podcasts as well?)

From what I understand, no. The initial purpose of getting podcast is not for advertising, but every minute someone spends listening to a podcast is a minute they are not spending listening to music that Spotify has to pay the music industry. They won’t embed advertising in third party podcast - for now.

It’s assumed that the second phase is to allow podcasters to embed ads to allow them to monetize their podcasts, but it will be opt in.

I feel like generic embedded advertising would be a step backwards in podcast monetization. It seems to me that interstitial adds in podcasts are incredibly powerful because they are usually in the voice of the pod-caster, so on average the listener is probably going to be much more attentive to the add since it's closely related to the content they're actively paying attention to. Without that people will just tune them out like every other ad

You probably spend most of your time listening to popular podcasts with a large enough listenership that they can get advertisers. There are thousands of smaller podcasters that can’t get advertisers.

Also, most podcast ads are for direct response ads where the effectiveness of the ad campaigns can be tracked somewhat via coupon codes and that either are for large purchases (Casper, Warby Parker) or for subscriptions where the lifetime value of the customer and churn rate can be estimated.

You don’t hear that many brand advertisements on podcasts. That’s the market Spotify wants to go after.

Besides, an advertiser doesn’t need fine grained targeting to know that for instance anyone listening to “The Talk Show” or “Accidental Tech Podcast” is a probably a computer geek with lots of disposable income.