If you’re getting ready to get create a map mashup, but you can’t quite decide on which mapping API to use, you may want to check out Mapstraction. Mapstraction is described as:
At present Mapstraction provides support for APIs from the following nine providers:
Check out our Mapstraction Profile for background on the API. You can check out all of the features that are available via the Mapstraction API documentation and there’s also a Wiki with additional information.
Some other things to note: