I would like to generally answer that NO it's not safe to just remove php-mysql and install php-mysqlnd, especially if you're not "a server guy". Because once I removed php-mysql I removed phpmyadmin along with it and that was quite a disaster.
I ended up (with help of Rackspace server guys) with upgrading my PHP to 5.4 (can't go to 5.5 yet until I convert all my code to use mysqli) and then manually forcing the install of php54-mysqlnd-5.4.17-1.ius.el6.x86_64
(http://dev.mysql.com/downloads/connector/php-mysqlnd/), because of the error while trying to do it "the normal way" Error: php54-mysql conflicts with php54-mysqlnd-5.4.17-1.ius.el6.x86_64
. Hope this helps someone.