Pros, the case is not bulky and has a loop on the back for going around a belt. It's (as another reviewer said) collapsible and branded, with a reasonably sturdy Velcro fastener. There's also a hole to feed a chain or strap through, which is a nice touch. Other than this hole (and the main flap) there are no other openings into the case, so it's certainly splash-proof. It's also well put together, and shows no signs of loose stitching or badly matched panels.
Cons, the case can be a little too snug - if you try to remove the camera by gripping the edges, it's easy to open the battery compartment rather than take the camera as a whole out. There is no room or pocket on the case I received, which is different to that reported by at least one other reviewer. As the collapsible sides of the case currently bend inwards it's possible to catch the various dials and buttons on the camera when putting it into or removing it from the case. I would hope that with use the sides will straighten and this will no longer be a problem. The case is not padded, so it's only reasonable purpose is to protect from scratches and dust. Don't look to this to provide much in the way of shock protection.
Overall, it's nice to have, but I'm a little disappointed that such a case wasn't included with the camera itself.
The case has a stiff front and back with collapsible sides. This tends to make it a loose fit which can be handy for a easy, blind return of the camera back after use. The downside to this is that it adds to the general bulk of the package, particularly when worn on the belt.
There is a small pocket hanging from the back inner side of the case. This will hold a CF card or, at a pinch, a spare power pack. Adding either of these pushes out the depth of the case, to its maximum extent with the power pack. If you have a decently-sized CF card you will probably, like me, find the spare pack more essential. It is possible to slide the power pack down alongside the camera but this is not at all ideal. A special pocket for this would have been better.
One other small gripe is that the velcro fastener seems to be a little feeble. I can see myself strengthening it for peace of mind in the future, if I don't spot a better case first.
The case comes with a belt loop & the camera cord fits through the case for carrying. The case is fastened with velcro at the top, and has space for a spare CF card inside.
I have not found a better case yet for the IXUS cameras.