Actually, it's DVI to HDMI. Pioneer plasma panel has HDMI, so I bought a DVI/HDMI cable, and PQ is better with this when compared to component, which is also hooked up and active at the same time.
I use the components because my TV doesn't support DVI. But if it did I would most likely still use the components because I can feed all my devices into my A/V receiver and then only one set of cables to the TV.