is it ethical to copy ideas from a similar site?
Tawheed: Blatantly copying is a bad idea. Understanding why they're different, and figuring out the motivations behind their (different) choices and then reflecting on the choices you've made for your product is a good idea.Jason F at 37Signals wrote about this a while back: http://37signals.com/svn/posts/1561-why-you-shouldnt-copy-us...