Well, Kraftwerk's official site has very little actual information on it. It looks good though

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I am as curious as you with regards to the DVD, I saw their show in Stockholm, very visual, so I'd much rather have a DVD than a CD (or even SACD) of this tour.
I do believe the german version will differ only in the lyrics sung (and in some of the song titles, since they are translated was well), but I'm not sure.
If you haven't alreday, you may want to keep an eye on
this unofficial fan and info site, they seem to have some more info, but nothing on the DVD, yet.