I took the Canon PowerShot A640 on a mountain bike ride this weekend and got to take some action photos with it. It's pretty good. It has an optical viewfinder which makes a huge difference for accurate panning, as you can see here. The flash is pretty good for a compact camera, too. And a full range of exposure options is nice. I shot these using the A640's shutter priority (Tv) mode.

Note: both of these photos have been heavily adjusted using Photoshop masked adjustment layers. This isn't because of any camera faults. I generally shoot dark to hold highlight detail. But it's important to point out that the images didn't come out of the camera looking like this. These do, however, represent the potential of the camera very well. And I would have adjusted the images the same way if I shot them with my digital SLR.