Ten thousand centuries.
About Elrond's children- when he leaves, they have to make their final choice about being mortal or not. There seems to be a thing running of Elrond's kids all being Half-Elven like him. But that's really more to do with the fact that Elrond leaving is synonomous with ALL the Elves leaving Middle-Earth, and the days of immortal beings there being gone.
I'm not quite sure about this. If i remember correctly Elrond and Elros were given the chance to choose what they should be.
Elros chose to be the first leader of the numenoreeans and elrond the elf side.
Why did i get the impression that that choosing was a favout..a particular case (because they're close blood of earendil..or whatever)
okay heres how it is, if you are born to and elf and a man than you retain the characteristics of the elves, you are immortal. now at the end of the first age the gods gave elros and elrond (both half elven) the choice to be man or elf. of course elrond chose elf and elros man. now in the third age there were 3 half elves (possible 4 if you count the lineage of prince imrahil who is "rumored" to have elf blood, who better be in the next movie) the three were eladan elohir and arwen (excuse the spelling) they took on the traites of elves and lived for centuries being born in the second age. but again the gods gave them the choice at the end of the third age and they all chose to be of mankind.
thats true, but i guess if you have any man blood you are considered half elven. i picked up most of that stuff in the silmarillion and the other books that come with the silmarillion, but there are also other books that explain things like "Unfinished tales" plus there is a series of 12 books that describe the evolution of each of the stories called "the history of middle earth". they are pretty interesting but very tough and tiresome reading.