As I'm from the Netherlands I think this is great news! Rate of adoption is skyhigh in Sweden, I'm very curious as to what the release will do for the way music is consumed in my country.
Now if only they would allow for some better playlist-management in their client, I'd be even more thrilled.
The biggest change in Norway was mostly that you're guaranteed to hear "Hi! I'm Jonathan from Spotify..." at any party where people haven't bought a premium-subscription. Everyone found out that Spotify is simpler, easier and more convenient than ripping CDs or playing the CDs directly.
They were looking for feedback on their playlist API at music hack day in Amsterdam two weeks ago. I think they're currently working on improving playlists in general.
Now if only they would allow for some better playlist-management in their client, I'd be even more thrilled.