IPhoto09 unable to open some jpgs

Question

After spending two hours with a Mac Genius, who was unable to help me, I'm hoping someone here can.
I recently upgraded to iLife09. I started having problems opening up some pictures in iPhoto. Here are the issues:
1) I can see the thumbnail, but when I try to double click on it, the picture will open for half-a-second and then just gives me a black screen
2) It gives blank screen on some pictures, but not all. They're pretty random.
3) I can find the actual jpg files in the iPhoto library, open the files ok in Finder or Photoshop and edit them, so I know the files are not corrupt
4) iPhoto09 is unable to open some jpgs, if I resave the jpg as tif or gif then reimport them to iPhoto09, it opens fine
5) The worst thing is that it's all random, it's unable to open some pictures in different albums, but I can't detect a pattern
6) This is only happening after I upgraded to iLife09
7) I sent the disputed jpgs to a friend, who imported them to her iPhoto08 and was able to open them just fine
Can someone help me please?

Answer 1

I don't see color profile in Tools, I see Match to Profile and Assign Profile. The default selection is Generic RGB Profile.
In any case, all the pics was shot from the same camera on the same day. iPhoto will only open some, but not all. If I open the jpgs out of iPhoto, like Preview, I can open them all. I can also make edits to all pics in Photoshop but when I reimport those photos into iPhoto, it will open some, not all -- basically same issue as before.