It seems that TinyGrab has pretty much imploded due to an attack. If you’ve posted screenshots in these forums using that service, there’s a chance some links in your posts that existed before TG2 was launched are dead. I’d suggest using DropBox (GrabBox) or other hosts for now.
Yes, TinyGrab is a mess right now and despite their posts that service has been restored, it still doesn’t work for me. I’ve used TG for a couple of years now, but I’ve switched to Skitch for now. Makes one wonder if this movement to near-total cloud storage is a good idea?