Non-rock? I don't know, they were often pretty close to rock. I would classify them as a form of pop rock myself, songs like I'm a Marionette and Does Your Mother Know are definitely 70's rock music.
Björn and Benny never really stopped. They've written several musicals including Chess, Kristina and indeed Mamma Mia since, and also done a ton of folk music. Agnetha and Anni-Frid have had solo careers, Agnetha had a new album in 2013.
One of the greatest bands of all time. I was very obsessed with them as a teenager, and I didn't hide it either which obviously made thinks tough for myself. I couldn't possibly name a favourite song, but The Visitors is an incredibly beautiful album.
I really wish we could get the full live show from the Australian tour in 1977 rather than having the videos being broken up into stupid crap from the terrible movie. I'm A Marionette and Get On The Carousel need to be shown in all their glory.
Had a massive crush on Agnetha for years. Benny and Bjorn's debut album Lycka is well worth a listen. They remind me of Simon & Garfunkel.