My own two are outside and have the run of the back garden during the day - I am a stay at home mum and hubby works in the conservatory so we have plenty eyes watching them! The only reason I wouldn't let them out in the winter is if it is very wet outside because I would worry about their coats not being dry before the temperature drops at night.
Something funny i have noticed is, they have a huge bed of straw and hay to burrow into but whenever i check on them, which can be as late as 1am, they are sitting downstairs on the concrete slabs :shock::shock::shock:
In terms of feeding and cleaning out it is the same all year, just a warmer coat and gloves in the winter.