I think it's the cable provider's fault, as I have the same problem, except it randomly comes and goes. The Sony TVs use a slightly different method of getting program info (they get their info from data that's usually transmitted over one of the public channels), which I think is why your Sony worked but the Samsung doesn't... at least I think they use a different method, because you're not required to tune to each channel as you are with the Samsung.
Anyway, for me, when I first got the TV it worked, then my cable provider remapped the channels and then it stopped working. Sometimes they map the channels back to where they're supposed to be and then I get program info, but then it switches back the next day :(.
Pressing the info button on the remote brings up a rectangular inset screen that wants to include program title, program description and prev and next cursor options. I am hooked directly to the active cable source and setup search found over 300 channels. The display will show the digital type ( 720p, 1080i/p, etc) and Dolby indicators, but it won't even display the program name. At least my dead Sony was able to ID the name of the program. I called Samsung support and the phone techs could not seem to help and one stated that the feature is no longer included in the OS. Could that be? Why would Samsung tease with the fields for the info and not engage the feature?