Originally Posted by tylerSC
Images appear sharper on 1080i stations. But 720p does possibly have smoother motion.
I think it really depends upon the de-interacer your tuner is using for 1080i. Quality can vary depending upon the combination of hardware/software. A TV chip, where there are cost considerations, might not do a very good job at de-interlacing high motion. A pc using hardware graphics and advanced 2x de-interlacing can be flawless in motion rendering.
Since most people have 1080p TVs and we are talking about upscaling 720p vs 1080i interlacing to generate the 1080p picture, I'd say that 1080i does look better given the above. Of course a lot also depends upon what is being sent from the broadcast station.