Go get yourself one of those 1GB memory cards so storage space isn't an issue on your trip, and just shoot shoot shoot, that's the main thing.
Get a high speed memory card. I have a 1 GB with 80X speed.
I went to a CAD-CAM software demo, where while they were waiting for someone to show up the conversation drifted to digital photography. I learned the slow recovery between shots, which was an issue with my old camera, was both a function of the camera and memory card. He said often people bought cheap slow speed memory cards, so the limiting factor was not the camera but the card. I probably bought a memory card faster than my camera, which is fine with me.
Another point, I have a similar Canon to Mike ... maybe it is the same, I'm not quite sure. The instruction book advises memory cards up to 500 Meg. I called CAnon and talked to a technical specialist, he said the only reason a 1 Gig card was not listed because it was not officially tested. However, he saw no reason why it would not work.
So far the most photos I have made between downloads was approximately 400. I ran out of battery, which I now have a recharged spare with me always, before I ran out of photos.
The battery recharger for my camera is good for traveling abroad 110/220, you only need an adapter for the American-standard plug for whatever plug style used in HK.
Regards,