As I understand it, the new version offers an increase in dynamic range for still images (14 stops!) but this version is only for the 5DIII and 7D.
Is it worth the switch? Well a big thing to be aware of is that Magic Lantern voids the Canon warranty. It is possible that Canon will not even service a modified camera or will charge you to restore the original firmware (which probably means a chip replacement).
For video shooters, I can understand the risk may be worth it as magic lantern does add useful functionality - but for an improvement in still image quality? Consider
- 5D (any version) IQ
is pretty close to as good as you can get with a DSLR already
- You may see some improvement in certain conditions and/or when pixel peeping, but are you going to see a significant difference in any practical use of the images?
- the software is currently alpha - do you really want to risk trashing a camera?
I think if I had a spare (ie 3rd body) 7D lying around unused I would give it a try, but not on a camera I rely on regularly.
There are always people who enjoy tinkering with technology and pushing things to the limit, and that's great but there's always a down side. Think of modified cars - you generally can improve aspects of performance, but there's usually a downside in terms of economy or reliability or maintenance costs.
Colin K. Work, Pixstel