TL;DR: upgrade node to v0.10.21
I upgraded to maverick yesterday and along with disastrous reset of php.ini and httpd.conf i also experienced failing grunt watch.
edgars@Freyr ~/D/n/s/server> grunt watch Running "watch" task Waiting...fish: Job 1, 'grunt watch' terminated by signal SIGBUS (Misaligned address error)
Solution was trivial – update node as well.
sudo npm cache clean -f sudo npm install -g n sudo n stable
Which resulted in node update to v0.10.21 (was v0.10.20)
edgars@Freyr ~/D/n/s/server> node -v v0.10.21