The latest beta of iPhone OS 4.0 and the accompanying software developer kit (SDK) has provided a vital hint about the future of video recording on the next iPhone.
Discovered by Mac Rumors the API call which is another name for a software hook available to developers clearly refers to video of a resolution of 1280x720 more commonly known as 720p.
The current generation of iPhones all record video at 640x480 also known as VGA and this API call is also clearly visible alongside the addition of the new HD version.
The ability to record 720p video would fit nicely alongside suggestions of the iPhone HD naming and also rumours of a high resolution display and the inclusion of a 5 megapixel camera.