The more popular results reflect a linking pattern that's from then (mostly linking to the curved Macbook Air style fake iPhone 4), rather than now (linking to the released phone).
Ah right, sounddust's comment framed me into thinking there were no pictures of the iPhone 4 (searchable with the terms 'iPhone 4'), despite previous commenters pointing out they appear after several pages of results. Sorry about that.
But it does mean sounddust's explanation is incorrect, since this isn't a matter of whether 'iPhone 4'-searchable post-WWDC images are indexed. The question is why the images are buried beneath several pages of results.
http://www.google.com/images?q=iphone+4&hl=en&safe=o...
The more popular results reflect a linking pattern that's from then (mostly linking to the curved Macbook Air style fake iPhone 4), rather than now (linking to the released phone).