The differences in Career Tributes in the movie than in the book
In the Hunger Games movie I think they left out a pretty important detail. Haymitch said that the Tributes from 1, and 2 were Careeers not teh Trbiteus from 1,2 and 4. I think that they should've said 4.
In the movie, Katniss killed Glimmer with the tracker jackers. In the book, Katniss killed both the District 4 Female and Glimmer.
How important i think it was
I think it was pretty important that 4 was a Career tribute because Finnick adn Mags were in the 75th Hunger Games and in thier previous games they were Career tributes and that's how they won. I think that the people that made the movie will have to write in Catching Fire that District 4 Tributes are usually Careers.