Is there a real difference between HDMI and component cables?
Between an HD-DVR and an LCD HDTV such as your Sony Grand WEGA you probably wouldn’t notice much of improvement in image quality if any. If you’re not using an HDMI or DVI-D interconnect between your video source and your display then you are using an analog YPbPr component video interconnect. You’re essentially correct that “YPbPr is for analog signals and YCbCr is for digital signals.” YPbPr and YCbCr are not “analog component inputs”; YCbCr is the COLOR SPACE FORMAT used for DIGITAL component video and YPbPr is the familiar color space counterpart for ANALOG component video. All digital video content on DVD-Videos, HD DVDs, and Blu-ray video discs is encoded as YCbCr component video. Using an HDMI connection between a digital STB, DBS receiver, or DVD disc player, rather than analog YPbPr component connection, would indeed eliminate one digital-to-analog conversion step as well as “one less analog to digital conversion” step when using a digital display such as a high-definition LCD
