prepare some questions, better focusing on the job responsibility so that you can show your interest and sincerity.

Since the meeting is so short, they obviously liked you and just wanted to check in to gauge your interest and possibly discuss offer, start date etc.  In that case, i would be prepared short blurb to reiterate your interest in the company, what you can offer to the company.  More importantly, be prepared to answer questions around offer package, start date etc.  When i hire people, i would usually extend an verbal offer to gauge the interest level before proceed with getting the written offer out. 

Best of luck

Did the recruiter tell you that this is your last round interview or they will still possibly have you come in for onsite? If it's the latter case, I would suggest not to ask about offer package yet and wait until onsite. Be sure to prepare short topics about your qualifications, your interests, and be sure to ask questions about the company to show your interest.

Best of luck!

Thanks for azura, juniebugca,gleaebb reply!

I just finished with the hiring manager.  Like you guys suggest, it is what he wanted to ask my interest, including the project, their working enviorment, schedule.  Of course, I gave positive answer.  Then he said, the decision will be made in 2 weeks.

I just feel a little disappointing,  I thought the decision will be made right after this interview.