Just read this and thought I'd share. It's very, very true. Basically, leave your ego at the door, listen to what others have to say, trust your instincts as to who's right and wrong and your stuff will be all the better for it.
Writing is like any other job. You don't go into it an expert. You learn from others and get better. And you keep learning and hopefully keep getting better.
Ah balls, just read what Graham says, he's better than me.