Google started to index images a lot faster and it now even highlights recent results by showing a small label like "1 day ago" or "22 hours ago" below the image. You can't yet restrict the results to recent images, but I'm sure that this feature will be available in the near future.
Here's an example of a query that returns many recent results. It's easy to notice that not all the results are from news sites, so the images aren't from Google News.
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