Surprisingly quickly, Canon has announced a successor to the justifiably popular S90, making it 5 better.
They claim a raft of improvements, but based on reactions I've seen to the S90 the most important will be the addition of HD video. In-camera HDR might be quite interesting if it's executed well.
Still missing is a hotshoe/external finder option, and the lens' wide end remains at 28mm eq. Unknown is whether they've improved the dismal battery life.