One question about the real interest - if it requires a Windows based PC (assuming a Msft OS would be more popular than Linux) to be on the same network running a "helper" application (but no extraordinarily complicated configuration files), is a program guide still of interest ?

Is this for display only (surfing channel info)? For integration with whatever TV tuner you have (DirecTV, Cable, etc) such that one could change channels? Search upcoming listings? PVR setting, etc? I assume the answer is "yes". It's one thing to generate a viewable, drill downable program guide. It's another to have it be general enough to be useable for all the features that everyone will want once they have access to the guide.