What are my rights if I was laid off and never called back when promised?

Unless you actually had a contract stating that you would in fact be called back by a certain time, or that you would get the first opportunity at any new job openings for which you were qualified, there unfortunately is no liability. Companies may tell employees that they would like to call them back or intend to call them back, but that, without more, does not create a binding contract or obligation that they will be called back.

Unfortunately, an employer is under no duty to cal back a former employee, regardless of what  they led you to believe.  Most employment relationships are what is known as "at will".  This means that you can work for an employer, or not, your choice.  In turn, the employer can hire or fire someone for any reason or no reason whatsoever.

Basically, the exceptions to would be if there was: 1) an employment agreement or contract (which governs termination); 2) a union or collective bargaining agreement (which governs termination); 3) an employee handbook or other official policy statement (which governs termination); 4) discrimination  (i.e. for reasons of race, religion, age, disability, sex, national origin).