Daniel Stone is apparently the XKB maintainer, but is not entirely sure how that happened. He fears the prospect of overhauling the input system, but feels powerless to stop it. He was previously the X maintainer for Ubuntu, and worked on Debian packaging of X also.

XKB FTW

XKB, the X Keyboard Extension is, at least in theory, a terrific extension that allows easy and sensible keyboard configuration. In practice, however, it offers many opportunities for improvement. This talk will outline my current plans for XKB, as well as some of the history of this rarely-understood extension.

Slides: http://www.fooishbar.org/talks/fosdem-xkb.pdf