I worked really hard to get an offer from a prestigious organization, and was ecstatic to accept the position. My friend at school was also applying for a job at the same firm. The hiring manager informally asked me what I thought of him. In all honesty, I don't think he's that smart and is not a good fit for the position he applied for. He is my friend, so I do not want to betray him. On the other hand what if I say positive things about him and he gets hired and is a total screw-up? Would this affect my reputation inside the firm? What should I say?