Originally Posted by carandol
I've started reading the Baen Books version of Time Traders, and discovered that it's been revised for this edition, as compared with the old out-of-copyright version available on feedbooks. Just minor things -- the bad guys are no longer the Soviets, but a resurgeant "Greater Russia", and there are rather less atomic-powered vehicles (probably a good thing!). Presumably this is to make them tie in better with the new volumes; it certainly makes them feel less dated.
That's not necessarily the reason for revision. The out-of-copyright versions of "modern" SF are almost always the original magazine stories for which copyright was not renewed. It was entirely normal for the stories to be re-written somewhat when republished as novels (which are still under copyright protection). You'll find the same if you compare the magazine versions of E.E.Smith's early "Lensman" books (for which the magazine copyright wasn't renewed) with the novel versions of the same stories.