I've just updated to the newest version (10.6.9) and certain shortcuts do not work, most notably for me Ctrl + I (for italics) and Ctrl + B (for bold), but other shortcuts like Ctrl + U do work...
Anything involving the Shift key doesn't work either, most notably the text resizing shortcuts Ctrl + Shift + ./, and Alt + Shift + D (date).
Some shortcuts clash, like Ctrl + M, it is both the minimize shortcut key and the indent shortcut key.