Not really. The only requirement, which is listed on the [url=http://www.dynadot.com/domain/api.html]API[/url] page, is
"Only one request can be processed at a time. So please wait for your current request to finish before sending another request."
It would be nice to see some type of exclusive membership where we pay a fee for more options such as being able to hit api requests as much as we want. Membership fees alone could probably lease you guys a nice server just for this.
api Acceptable Use