Great question...I had to look this one up. www.faa.gov/air_traffic/publications/atpubs/pcg_html/glossary-m.html (scroll down to the definition) says the MSA is at least 1,000' of obstacle clearance in a 25 nm radius. This also confirms it, directly from Jeppesen! www.jeppesen.com/download/aopa/mar99aopa.pdf It seems I misspoke, so I appreciate you asking!
