It seemed odd to me that people around me seemed to be able to felt just fine with top loaders but I only with front loaders.
Talking to a lady at the library knitting club last Saturday I found out what the difference is. It appears that the standard American washers don't heat the water like their European counterpart, but use water preheated by a water heater. This explains many things, like why American washers are much faster than European and why they only have cold, warm and hot settings and not the actual temperature you are washing with.
So in Iceland I threw the objects in the washer and they came out all felted and nice. Here I throw things in the washer and they come out all limp and pathetic :(
But the 'felt-by-hand' method seems to work for me so I'm just gonna stick with that (and keep my eye out for a water heating washer).
p.s. does anyone know what are the temperatures behind the cold, warm and hot? Does it perhaps depend on the water heater in question. If you have a formula for it, all the better :)