I was able to sync my gg.deals collection with my Steam account 3 weeks ago, but when I do it now it comes back fairly quickly and I get a message that says "There was a problem with synchronizing your Steam collecti...". If I click on that message it just goes to my collection page with no further information on the problem. I had no problem syncing my GoG collection, nor do I have a problem with syncing my Steam account with isthereanydeal.com.
Also, I was sent a confirmation email when I signed up for this forum, but when I clicked on the link in that email I got "Invalid confirmation token".