Apply online and receive call from Recruiter for prescreening, next step is interview with Branch Manager

Received a call from the recruiter within a couple days of submitting my resume on line. We set up a time for phone interview. It was brief couple of questions about my work history. Then a call later on that afternoon to set up a time to meet with the hiring manager, this guy is resposible for all the Sun Trust branches in the area. First he was 15 minutes late to the interview. Ok, he did a good job explaining the position almost like he was trying to sell it to me. He asked about my work experience, situational type questions, but the interview was more conversational, me explaining the things ive accomplished. This job was an excellent fit based on my skills, I basically aced the interview he and i knew it. At the end of the interview. Hiring manager was excited, i was excited and he told me everything was good and i should hear from the recruiter. I thought the only thing left was for the offer. A week went by and no contact from them. I sent him a thank you note. The day he received the Thank you letter, i received an email saying they were interviewing other candidates and i didnt get the job. The only reason i can think of why i didnt get it is he said he knew a couple of people from my current job and i believed he contacted them and i have no clue what they said, obviously it wasnt good.