llona: Yes, the prince is a frog but a big part of the story is that when Tiana kisses him, she turns into a frog also. I'm pretty sure they mention that in the trailer.

The Princess and the Frog
Trailer
(2:25)

I just hope the first black princess doesn't spend most of the movie as a frog, that would be kind of... I don't know, cheap and disappointing.

The Princess and the Frog
Trailer
(2:25)

The Last Airbender
Teaser Trailer
(1:41)

The Princess and the Frog
Trailer
(2:25)

The Stepfather
Trailer
(2:35)

The Road
Trailer
(2:31)

Nine
Trailer
(2:30)