If we had a 'like' button how long do you think it would take before people start selling 'likes'
As redsn0w said, maybe good to avoid the +1 post but not really useful.
No, I do not support this idea. If you want to have 'LIKE' button you can use Facebook. I do not use facebook and would not want that button here on forum.
I haven't read the other thread HeroC mentioned, but it is my impression that the "like" button won't actually influence what posts you are shown in a thread; it will merely show some sort of indication that others appreciated your post. Perhaps that could lead some campaigns to try and work with this new system, leading to "like" buying, but I don't see that the overall forum experience would be negatively affected by this.
I wonder if a more specific set of buttons would be a good idea though - instead of one generic "like" button, a few buttons, like: "useful post", "made me laugh", and so on.