To your other question about "reach some kind of deal", it's easier said than done as each company has competing priorities in their quest to maximize profits. I'd guess we're not seeing Spotify in the M3 because Spotify wanted too much $$$ for the license (and B&O's cost analysis said not worth it for their "budget" device - customers can just use Chromecast... Naim and other high-end brands get away with it), or, possibly, Spotify has changed their API one too many times, and, again, B&O's cost analysis said not worth the development spend to try to keep up.
Speculating on the other services, that would be any service that they currently support - Deezer, TuneIn. Reading between the lines, it is saying we are just one API change or license renewal ($$$) increase away from B&O saying "not worth it".