Make sure to have ALL documents required/asked during the interview.
I submitted all asked at the NVC during the earlier stages of the petition process thus during the interview none were asked anymore.
Make sure to have submitted ORIGINAL NSO DOCUMENTS, VALID NBI Clearance (check to see if it is still valid during the time of the interview, if not, secure a new NBI Clearance), FORM I-864 and ITR and W2s of petitioner (2011, we also submitted ITRs&W2s for the last 3 years).
Filipina Prescreener was very nice, asked a couple of basic questions. Just validating what was on the DS 230 Forms. Asked to see our pictures too.
Female American Consular Officer was nice and cheerful. Questions asked were my (1) husband's date of entry in US and on what visa (2) his job
She asked to see our pictures then commented on our E-session pics at Manila Yacht Club and my wedding gown. After that she said I was approved, I smiled and said thanks.