This wasn't my question (though I only recently replaced an older Mitsu HDTV, so it might have been just a short while ago!), but I still appreciate the informative answer, Scott. Thanks. Good to know that 2011 Blu-ray players no longer send HD via component, and that upconversion only works via HDMI.
So if I have my Wii connected to my Pioneer AV receiver, I should definitely have the signal output to the TV via HDMI, right? I'm assuming 480p (and not just 480i) gets upconverted...