SEOs thrive with data and even better SEOs have ways to automatically build software that uses this data to improve their conversions. Dynamically creating new pages based on search query data or A/B testing landing pages based on bounce rates and conversions in an automated fashion, simply makes sense. There are just an incredible amount of opportunity with this new API and SEOs are excited about it.
To be fair, most SEOs who realized this benefit already built internal systems to handle most of the tracking and dynamic creation of content and landing pages. But maybe Google Analytics gives them new ways to peal away at the data that they haven't had the time or resources to get at as of yet?
If you have technical questions about the API, you can check out the new Google Analytics API Group. There is a dedicated Googler there to help.
Forum discussion at WebmasterWorld.