Syntax and historical merit aside, I think this is one of the coolest names for a programming language ever.
Technical/mathematical German has - to me as a native German speaker, at least - a sound to it that is somehow ... neither cool nor uncool, actually, it somehow transcends the entire concept.
I don't think Zuse had AI in mind at the time. The planning would have to be done by the programmer.
This also fits in better with the fact he invented (or at least envisioned) a "Planfertigungsgerät" (plan preparation device) to convert the "Plan" from human-readable notation into something the computer could run (effectively, a compiler).
There's part of me half expecting some HN'er to pop up and tell stories about cutting their teeth on a Plankalkül code base as a young whipper-snapper.
...and an incomplete js transpiler (), and a heated discussion about how exactly the TIOBE index is unfairly skewed against plankalkül.
( implemented by comparing the provided source against any plankalkül implementations that might exist on http://www.99-bottles-of-beer.net/ and emits the highest rated js implementation if it matches, undefined otherwise)
Here is a paper that describe the Plankalkül in more detail.
* R. Rojas, C. Göktekin, G. Friedland, M. Krüger, Plankalkül: The First High-Level Programming Language and its Implementation. ftp://ftp.mi.fu-berlin.de/pub/reports/TR-B-00-03.pdf
http://www.catb.org/retro/plankalkuel/figure3.png (found with other info onhttp://www.catb.org/retro/plankalkuel/)