I saw this a while ago, and I've spent the whole time since then explaining hopelessly why it WOULDN'T have worked.
-> By the time Frodo made it to Rivendell, there was no hope of reaching the eagles in time to make any kind of plans with them.
-> The entire purpose of the Fellowship was to remain hidden from view of the most powerful Evil in the world. Bringing 3-5 gigantic eagles across Middle-earth bearing The One Ring would have made it, oh, about 30 feet without Sauron noticing and sending the Nazgul out immediately on fell beasts. The eagles wouldn't have made it all the way to
Mount Doom, the Ring would have fallen/been lost again and nothing would have resolved.
-> That quick of an approach to
Mount Doom would have accelerated the corruption of whoever bore the Ring. They'd have gone nuts and claimed the Ring.
There are some more points I could make. I realize you weren't asking for a harsh rebuttal; it's just that I've been waiting a long time to make my case before other LotR-savvy individuals. Yes, I'm a
hopeless geek here.