I have worked with Google maps a few times and I really like it. It adds so much to the site and really helps out the users.
The first time I used it was for a site for Accomodation in Bergen called The Elfhouse or Alvehuset in Norwegian. The only problem I had was that Google don't give you the longitude and latitude for points on your map so to configure my Google map, I went to YourGmap and even though this is a great map solution in it's own right, I used it to configure my Google Map.
I just did a new map for my sister's hockey team's website, Guinness Ladies Hockey and everyone was very pleased with it.