iPhoto is great. Even with my 14,000 photos, and over 400 different keywords, its still speedy. However, great is the day when I find out something new about a program I already love. Although the day I found this was a while ago, my good friend Mike the other day asked me whether it was possible to browse the photographs on a digital camera in iPhoto prior to importing them, and I remembered this great tip.
If you want to browse your camera photographs, just plug in your camera into your Mac, (iPhoto should open automatically in import mode), and instead of clicking import, press the return key on your keyboard twice quickly. This will let you see all of your photographs on your camera, and on some (probably most) cameras, you can drag and drop into your iPhoto library.
This is a cool little trick courtesy of MacOSXHints. If you want to find out more, I highly suggest you visit their incredibly helpful site.