Much of what we're seeing takes what is traditionally editorial content (i.e. playlists, reviews, concert listings), and wedding it to the Spotify music platform. For example, Jann Wenner of Rolling Stone explained that the magazine and artists will be creating and curating playlists in the company's new app, and the music backend will be provided by Spotify. The platform will be available to developers, who will be able to build HTML5 apps on top of the service.
Spotify is also rolling out an iTunes-esque 'App Finder' in order to help with finding Spotify-integrated apps and curation services.
The term "app" seems to have been applied loosely here. A Spotify "app" isn't as much of an app as it is a playlist, or some other interface with Spotify's music. Having said that, the current selection may just scratch the surface in terms of potential.
Considering Spotify's long-term prospects have recently come under-fire, it will be interesting to see what effect this has on consumer and media confidence, and whether the use of buzz words like "app" will bring any further users to the platform.