LCD - both have a large 3" LCD
sensor - both large - similar overall performance
RAW - both capture in RAW as well as jpeg - (not used yet)
underwater housing - both give good access to manual controls
autofocus tracking - both have - (tried but don't like)
scene modes - underwater - Canon = 1, Olympus = 2 - (I prefer shutter prioity)
shutter speeds - Olympus only slightly faster
image stabilisation - both have - Canon might be better?
screen/ LCD clarity - mixed reports
good high ISO performance - mixed reviews
lens quality - mixed reviews
underwater housing - (own manufacturer) - both have
about 4x zoom (more than I need)
lag between pressing shoot button and photo being taken