Avatar is James Cameron's first feature film since 1997's Titanic, and one of the most keenly anticipated movies for years.
The science fiction epic has been filmed using a mix of CGI, motion-capture animation and live action, and will be shown in stereoscopic 3D.
Speaking as a 15-minute trailer was released, the director spoke about the challenges of making a film using cutting edge technology.
We asked for your reviews of the Avatar trailer and preview. Please find a selection of your comments below.
I went to the world's first screening at the BFI Imax, and I felt sick watching the 3D footage. The use of stereoscopic 3D and the CGI motion-capture does not work well with Cameron's swooping, jerky camera movements. It feels like you're riding a simulator rather than viewing a film. That said, the visuals are fantastic - a real leap forward in film-making technology.
Seb King, London, UK
I watched the teaser trailer yesterday after months of hype and it definitely delivered. The CG environment is stunning and this is surely to be the next step in 3D technology. Going to watch the footage later so will see how good the technology really is. It's 14 years in the making so I know it will be amazing!!
James L, Sheffield
Just seen it - pretty amazing. Been following Avatar for the past two years - only slightly disappointed that when the camera moves it becomes pretty blurred and it's hard to focus. That said, the scenes where the camera doesn't move so much are amazing
Paul Dixon, London
James Cameron has made an original epic that looks visually stunning and beautiful. I was sceptical about 3D technology until I saw Avatar footage first hand at movie-con 09 and was pleased to find my senses being spoon fed something truly special and unique. Lets hope the four years in production and $200m budget make it as epic as we expect.
Lawrence Cooke, Staines
I have seen the trailer on High Definition and thought it looked amazing. I cannot wait to see it on the big screen in December! It's great to have something new and different to look forward to.