I've been here for several years and have seen it happen many times. The majority opinion on these forums about the iPhone 4 before it was released was that the seams along the edge were hideous and "un-Apple like." Then it was released and suddenly everyone loved it.
The iPhone 5's two-tone back was considered hideously ugly before it was released (this was the majority opinion in these forums). Now, everyone keeps saying the iPhone 5/5s is so elegant lol. Now, people are attacking the iPhone 6 design because of big bands on the back, and the iWatch will be no different. Again, once they are actually released people will get used to them, and by this time next year the majority opinion will be that they're beautiful.
If you're actually asking for specific posters who have changed their opinions, it would be a little difficult to sift through the millions of posts here.