This is quite different.
These are my experiences.:
Vectors and videos are selected mostly quick. (1h - 5 days)
Photos can have a waiting period of 1-10 days.
Thanks for the question Doug. Content is reviewed manually in the order it is received. The wait time will vary based on the number of images in the queue. Currently the average wait is between 3-5 days. If you have images that have been waiting longer than that, feel free to reach out to me directly (include an image ID number) and I'll be happy to take a look and make sure everything has been submitted properly.
Thank you Mat, the image IDs that have been waiting 5 or more days are 121904355, 121951553 and 122249085
I found that your account had not been validated when you created it as an important step had been missed. I have corrected this for you so your content should be placed at the top of the queue and will be reviewed shortly.
I was wondering if I can get assistance on a similar issue. File ID: 150401436 is at 6 days past submission and still in review.