When you pick up your copy of The Princess and the Frog tomorrow keep a sharp eye out for the usual easter eggs.
The usual Disney stuff:
At the beginning in Charlotte's room you can see a tea set that is meant to be Mrs. Potts and her children. You can also see Cinderella's coach.
The leaf boat used in the bayou is the same leaf boat used by Bernard and Bianca in The Rescuers.
You can see an Ariel like mermaid at the party.
The star Evangeline looks like the star from Pinocchio.
Early in the movie a woman is shaking the rug from Aladdin out on a rooftop.
Doctor Facilier's home is under the exit to club 33 (an exclusive club at Disney.)
Genie's lamp shows up during the "Dig a Little Deeper" song.
Ron Clements and John Musker are tossing beads from a float in the Mardi Gras scene.
You can also see a King Triton float!
Other than the easter eggs (and supposedly there are more) there are lots of people in mermaid/fish costumes!