I also like the idea. We have similar schemes running over here. People can just volunteer to take dogs out and spend some time with them. The shelters are specially pleased when people offer to do that for older dogs that usually wait so much longer for adoptions. They insist though that people are consitant and take "their" dog out on a regular basis (at least once a week every week). This schemes have been succesful, it is beneficial not only for the dogs but also for the people who are not in the position to have a dog of their own.