So I don't think they're made up at all, seeing as how they're in common use. It's probably true that there is not a black or white line between the two, and both can be good businesses, but I did think it fair to point out that cleaning is very much a "service" whereas 37 signals started out doing services (sites and so on) and moved towards products, which tend to scale up more.
Product business and service business are fairly common labels.
http://swombat.com/2011/4/26/services-products
http://techcrunch.com/2011/04/24/what-should-you-do-with-you...
So I don't think they're made up at all, seeing as how they're in common use. It's probably true that there is not a black or white line between the two, and both can be good businesses, but I did think it fair to point out that cleaning is very much a "service" whereas 37 signals started out doing services (sites and so on) and moved towards products, which tend to scale up more.