In Snow Leopard, Image Capture allows you to set a default application to open on a per device basis.
Snow Leopard is abound with small tweaks here and there that are really quite nice. I just noticed a new one this morning that is very useful.
In previous versions of OS X, you could use Image Capture to set a preferred application to launch (or not) when you attached a camera to the Mac. My first run-in with this preference came because I wanted to disable iPhoto from launching every time I connected my iPhone.
The common complaint with how this worked in Leopard was that Image Capture managed this as a global setting, i.e. I could tell my Mac to not launch iPhoto when any camera was connected, but I couldn’t say don’t launch iPhoto for my iPhone, however do launch it for my Canon DSLR. This led to some fairly clever, but hacky workarounds requiring Applescript.
However now in Snow Leopard, Apple has updated Image Catpure so you can set this preference on a per device basis. A small tweak, but much appreciated.