I wasn't aware of Magic Lantern (until I just looked at it). I'm curious, is it legit? buggy? In other words, I always worry about third party downloads -- I don't want to mess with my new pristine camera...
Magic Lantern is for me the one reason I keep using Canon, even if Nikon is less expensive and arguably up on par or even "better" these days in a feature-per-dollar comparison. ML is a firmware addon that originated in the video community but has many features for stills shooting. It does have some "killer" features, here's what I use:
* raw histogram and zebras so you see if the shot is really overexposed, Canon histogram is only for jpeg
* auto iso function that also works with flash enabled and has a settable min. aperture in Tv
* helpful overlays in live view like focus peaking so you exactly see what is in focus
* dynamic range boost for up to 14 stops for video & stills for high dynamic range scenes
* up to 60 fps for raw stills for a short time, though at reduced resolution
* focus stacking for macro
* intervalometer for time lapses
* unlimited, automatic bracketing (though your 5d3 already has 7 brackets which should be enough)
* auto-ettr (expose to the right) for optimal exposure (less noise) and clean shadows
... and last not least ...
* 14-bit uncompressed raw video shooting which is a stunning ability for any dslr and makes a big difference for recovering shadows or high dynamic range scenes
Concerning stability: Yes, the 5d3 port is still labeled "alpha", but it's stable as far as there should be no chance to endanger your new camera. The very extreme and also unlikely thing that can potentially happen that the software freezes your camera, which means you simply have to take out the battery and re-insert it, problem solved. After getting to know your general 5d3 you should give it a try if you are the curious kind of person that like to experiment a bit.
Oh, okay. Thanks. I will keep my eyes on it. Can anyone suggest any other good forums to continue to learn more about my new camera? Everyone has been just great here - but I have a feeling I must be taking up "space" since I'm not discussing "rumors" anymore.
On the contrary, the forum title is misleading - the main page is about rumors, but the forum is about photography in general. There are always trashy fun "When will the 7d2 arrive" threads, but actually these rumors make you realize what your current camera does, doesn't and how to work around shortcomings. If you want to discuss technique or your pictures, just add to or open a thread in another subforum like "Canon general", "Lighting" or share your pictures in one of the existing threads.
I found this site very helpful for learning since there are a lot of people with experience and knowledge around who share it, and in contrast to other forums the tone is (nearly :-)) always nice and civil which makes the decisive difference to other forums I have looked at. Plus it's Canon only here, so there's less noise from threads you don't care about unlike in boards that cover all manufacturers.