I know this thread has been around for a while but I thought I would post some of my thoughts and recent findings.
The first thing I will say is thanks to everyone for all the great posts on the topic. Awesome information--Thanks for being the pioneers!
I have been thinking about how I wanted to proceed in my Camry. My initial thought was to purchase an RCA cable that has a female at one end and something else that the other end--I don't really care about the other end because I am just going to cut that end off and solder that end of cable to the identified pins from the computer cable. Then for power I was going to add some wire to the pins from the computer cable and terminate those ends with something that I could use as a "quick connect" for power to the camera. The reason I wanted to take this approach is because I don't have a camera yet and I just purchased the XM kit for the car that I need to install. So rather than tearing the dash apart twice I thought I would just have the backup camera wires under the dash so when I find the right universal camera I can install it easy.
I am pretty picky about the way the camera will look installed. One camera I am interested in is the Crimestopper SV 6300. It looks like an OEM camera and can be painted to match the car (which I like) and it is relatively cheap and can be purchased from multiple sources.
Today I was browsing the web and came across a "kit" designed to be installed in the Gen6 Camry. It is from a company called Rostra. My thought is that it is basically what I have described above--universal camera with the "customization" for the specific car. I have attached the links that I have found for this camera kit. The kit is listed at $309 on their website but I found a place called M&R Electronics that says it is $199.
Link to the specific page on their website where you can find the camera kit (should be the second one on the page):
http://www.rostra.com/RearSight-NavigationInterface.asp
Link to the installation PDF:
http://www.rostra.com/pdf/Form5103-250-8076.pdf
Link to M&R Electronics:
http://electronman.stores.yahoo.net/camry20062007.html
Thoughts? Comments?