I don't see why an exception shouldn't be made for Curious Labs. They certainly don't abuse the privelage. Their announcements here are concise and infrequent. The only ones in the recent past that might have seemed like advertising were the announcements regarding the buyout by the Shade company, but that's big news regarding the survival and future of the app, it didn't seem out of line to me. Although I don't get upset about it I have noticed that some merchants post work-in-progress images and blurbs here without specifying whether or not the product will be commercial, or claiming "I haven't decided." Unsurprisingly, when it's released, it's commercial. There hasn't been as much of that lately.