the following is from his official site
Peter's entire catalogue has been re-mastered to produce the best quality CDs and also to be ready for the new formats of DVD Audio and Super Audio CD. We also hope to re-release the whole catalogue on Vinyl throughout 2002.
The process of re-mastering is huge and saw PG and his music engineer, Richard Chappell, as well as Tony Cousins the mastering engineer, working day and night at London's Metropolis Studios, using cutting edge music technology.
When the albums were originally mastered Vinyl was the principle format. Because record players can track more complex music better at the outside of the disk, the running order of SO was determined by the format rather than by Peter. So there may be some subtle changes in the re-mastered versions.
As Richard Chappell explained, due to the increased sampling range of the new formats there is a noticeable increase in clarity and definition especially at the bass end of tracks.
The Peter Gabriel re-masters will be released between February and April 2002.