You mean like in a println call? Yeah I believe it does. Actually... I seem to recall that you can actually use the $ in a variable as well in Java, but its not recommended practice (especially now that it would like a lot like PHP objects).
Don't quote me on that, but I believe that yes it will print normally without needing escaping, and that it can be used in a variable name.
Just give it a try, worst comes to worst you'll need to escape it.
As of PHP 5.5, the MySQL library has been officially deprecated. It is recommended to move to either MySQLi or PDO libraries for your mysql connectivity. See here for help choosing which interface you prefer: http://php.net/manual/en/mysqlinfo.api.choosing.php