Executive orders have been around since the time of George Washington. Lincoln used an E.O. to suspend the Writ of Habeas Corpus and issue the Emancipation Proclamation. Eisenhower used them to desegregate schools. The list is long. Executive orders are designed to give direction to governmental agencies as to the execution of their lawful duties. They are not designed to legislate, but rather effectuate legislation or Constitutional provisions/protections. Obviously, in the two examples above, Lincoln and Eisenhower felt they were enforcing Constitutional protections.
I have not had an opportunity to read President Obama's new E.O., and I am disinclined to take guidance as to it's content from news agencies. So, at this point I can't comment. But as a fair guess, I'm probably not going to like it.