Well, I sometimes love FI. I had been wondering why certain clips at the stores looked so real (the dreaded soap look), like I've seen a U-571 clip in the sub that seems to show up in many demos, that I really like with 120Hz FI on. It looks so immediate and real. I recently bought a 55" Samsung LED and I have been able to play with the FI settings. I think I really like it on when certain genres are playing. I really seem to like it with sci-fi, most action, and horror and of course "live" TV and animation. I don't like it with more "serious" fare, like drama, "period" pieces, comedies and just when it doesn't seem to visually suit the piece. I have an Epson projector right now and sometimes think I miss it when I'm watching, so yesterday, I ordered a new JVC HD550 which has FI.
Hmm, but I also saw Dark Knight then on a JVC HD350 (they didn't have the 550 in stock) and didn't mind no FI at all. It was gorgeous the way it was. I guess time will tell.