> What do you mean by "no need for signal switching"?

If one has multiple sources of video/audio, let's use my actual example of I used to have: DVD changer, TiVo and DiVX player, then one needs a receiver that accepts all these connections and can switch the video/audio signal depending on which source is being used. Now HTPC replaces all these sources, because it can perform all of their functions. Therefore only amplifier is necessary, the receiver switching circuitry is unnecessary.