I have to argue with this last comment kimmills.
The right nursery/childminder can provide wonderful all round developmental programs, and cost and convenience wise if this works for you then great.
However, having a nanny can bring infinite benefits. The convenience, one-on-one personalised care, flexibility, and love for the job could actually prove more beneficial. Plus the fact that a nanny will get to know your children, give them hugs when they fall over, and hopefully remain a part of their life forever.
I am a qualified Montessori teacher who chooses to nanny, and I put an exceptional amount of effort into all the activities I do with my charges. I make sure they are exposed to a variety of stimuli, get to ask a million questions, and for as long as the children have an enthusiasm about a subject it can run for weeks!
When training, I did a placement at a highly regarded nursery. Right at the start I was told "If OFSTED ask, this is what we say" they had a variety of untrue answers to questions - I was horrified. Children "followed" the EYFS by having a few minutes a day with the most experienced teacher where she would stage and photograph things for the children's learning records. They children had fun, and were kept safe, but I was completely unimpressed. It was a money machine.
If you can find a good nursery, by all means take advantage! However, I love being a nanny, and my excellent references prove that my charges really do benefit by having me around. All of my nanny friends are the same.