The eagles will be released in January, thanks to those at Warseer for the pics of the 40k stuff that did not exactly cut off The Hobbit releases from the next page. Looks like Gwahir will be finecast and the regular giant eagles will be plastic. Based on pics from the hardcover rulebook the plastic eagles look pretty nice.
I participated in Red Box Games Kickstarter earlier in the year and just recieved my pledge packs. They are very well detailed minis. Cast in what appears to be something similar to finecast. I will take some pics and post them up once I am done ....multitasking. These minis are exactly the same scale as GW LoTr and would make excellent replacements for some elites from GW.
Below are front and back pics as well as pics of a size comparison.