TV recycles old material all the time. Magnum, The FBI, Hawaii 5-0, McGyver, Dynasty, Gossip Girl, Walker, Charmed. I haven't seen any of the reboots, but somebody out there has to be watching them.
A few months ago J. Michael Straczynski announced that a complete reboot of Babylon 5 is coming. His rationale is that he's grown as a writer since the original series. He wants to see how Babylon 5 will be now that he's armed with a deeper toolset. I can respect that.