I've heard from a source that Canon may be discontinuing the SX100 any day now. The hugely popular camera was price dropped significantly 6-8 weeks ago before the Panasonic TZ5 hit the street.
Improvements the camera could see:
The usual megapixel bump
Self popup flash
Viewfinder (not sure how they'd fit it on)
This could mean there will be some announcements by Canon in June.