helleborine - 9:05 pm on Jan 31, 2013 (gmt 0)
Forget about unified protest through blocking googlebot, there will always be opportunists who will not block in order to get more referrals.
For me, that's not a protest.
I've had to deal with several image hijack exploits this year. I'm blocking my site from Pinterest but now pinners are pinning from Image search directly. Also scrapers are using the Bing search API to propagate even more infringement. With more and more pinterest clones to deal with, it's getting worse every day.
Blocking the bots from my image folder solves all these problems.
I have a following, my visitors will find me, including through regular search, where I'm getting 99% of my traffic.
I had hundreds of images that ranked very highly in Image search, but for 150 visitors per month the above-mentioned headaches aren't worth it. Two years ago these same ranking images brought me 10K visitors.
It's a permanent decision for me unless Google provides a more elegant way to stop full-size image hotlink display.
Bing is blocked until they abandon their scraping-API, and that won't happen, so that's permanent for sure.