dh and I talked about this a lot and came to the conclusion that with nurseries you were more likely to get an adequate experience but with childminders you could get a fantastic one or an awful one.
We went with a childminder after trying a nursery for two days a week when he was 9 months old.
The nursery was absolutely fine and ds seemed happy there but I wanted him to 'love' another person. If I or dh weren't there I wanted him to have a person he felt especially close to. We decided on a childmnder for that reason. However I do know other parents who specifically chose a nursery because they didn't want their child getting too close to anyone else.
When ds is nearer to 3 years old he will start nursery but it will probably be part-time and I really hope that he will spend the rest of the time on my work days (3 days a week) with the same cm. I want him to come home from nursery to someone he knows and loves.
In the end the choice is so individual we can only give our own experiences but the final decision is up to the parent of each unique child.