Oddly enough, CDs use PCM.
On the topic of 'high end' samplers - actually these days just about all wavetable systems use multiple samples - there's more to it than simply using several samples to remove artifacts. Many instruments have changes in the harmonics generated at different pitches. These changes are across the duration of the note, from the attack phase all the way through to the release phase. By using multiple samples (and a few other tricks), it's possible to have a pretty accurate representation of the harmonics that colour the notes.