How can I browse photos on iPhone in Mac OSX?
The Image Capture app allows you to browse the iPhone's photos, albeit not at full size or resolution, without first downloading the image files to your computer. Image Capture also gives you the tools to download all or selected subranges of the photos on your iPhone, as well as deletion.
use ibrowse its free and quite straight forward
http://www.ibrowseapp.com/
navigate to the Media\DCIM\10*APPLE folders to find the camera roll photos
iPhoto will show you a preview of the photos on your phone, and you can view the photos without importing/downloading/transferring/etc.