Personally I also believe in the idea of that there is no death, only change. What also means there is not the eternal rest some lust for, sorry
I believe that, if we die, eventually something else will rise to support your consciousness. It might be in a totally different universe and time, but that will happen. It will also happen immediatly after death, since we dont notice time passing then we are dead
I think after the first century you'd simply go mad, imagine 100 or so years of memories, wars, historical moments, with the gift of living forever wouldnt that give you more license to interviene in global events?
Im not sure about it, living forever would involve super-human, possibily god-like powers. After all being the supreme ruler of a world is the only way to assure eternal life on it. Assuming it was just the enough to allow eternal life on earth, I think it would involve the intelect necessary to handle so much information... off course, we could as well end up having just human minds that burn out whats older