Even if it were open source, the camera's far too expensive to make it worthwhile.
I have some new thoughts on light meters, after having to shoot without one in the past 3 months or so, because of a broken light meter. I didn't have a small digital point and shoot nor a phone camera (my phone is a 7 year old Sony Ericsson), and so I relied on either sunny 16 or my Canon Powershot G3 for gauging exposure.
The Canon was huge and heavy (for a lightmeter), and switching it on just to take a reading was quite troublesome. My new selenium cell lightmeter just arrived and I'll certainly be using it. I doubt, however, that it will be as accurate, especially in a low light situation, as the digital camera.
Bill Mattocks said it best in another thread when he said that if you can afford the weight and mass for a spare roll of film, you can carry a lightmeter. I tend to get obsessed about size and function, though, and it just seems such a waste to me that all these phone cameras can't give out basic exposure data.
Clarence