The Boys are outside in a converted aviary/shed set up - they are nethies, so diddy, and they have a lot more space for bombing around in than they could have indoors. They like digging in their gardens too, and to be honest, even though I would love to have them indoors, I think they are happier outdoors. There are 4 of us in the household, and we spend a lot of time in the garden at different times, so they get a lot of attention. Even on wet days I go down at least 6 times a day, usually more.
Her Ladyship is my bedroom bunny, and she DOES NOT do outdoors! We did try her outside for some fresh air the first year - we put a run on the grass, and she spent the whole time sat on the wooden ledge, refusing to put her feet on the ground. She loves her carpet and fleecey blankets etc - I could never house her outside.