Notice all the app and driver incompatibilities suddenly listed due to the 64bit migration… now imagine the hue and cry if there were all these cool end user features in Snow Leopard that people “had to have” but couldn’t because app x or y  won’t run, or the printer can’t print, or …

So, instead, position the release as a (mostly) under the hood prep for the future. Get that message out and accepted well ahead of time. And bingo! Very little noise (relatively) about incompatibilities now.

Clever.