O que aconteceu com Saruman depois que ele foi esfaqueado por Grima?

To the dismay of those that stood by, about the body of Saruman a grey mist gathered, and rising slowly to a great height like smoke from a fire, as a pale shrouded figure it loomed over the Hill. For a moment it wavered, looking to the West; but out of the West came a cold wind, and it bent away, and with a sigh dissolved into nothing.

Está muito implícito nessa passagem da Lavoura do Condado que Saruman tentou passar de volta a Aman, o Ocidente, mas foi negado. Dado que ele foi negado e que, tanto quanto sabemos, Eru não entrou para bani-lo do tempo (como por Morgoth) ele teria percorrido Arda como Sauron faria:

his fall will be so low that none can foresee his arising ever again. For he will lose the best part of the strength that was native to him in his beginning, and all that was made or begun with that power will crumble, and he will be maimed for ever, becoming a mere spirit of malice that gnaws itself in the shadows, but cannot again grow or take shape.

Quando Saruman é morto,

To the dismay of those that stood by, about the body of Saruman a grey mist gathered, and rising slowly to a great height like smoke from a fire, as a pale shrouded figure it loomed over the Hill. For a moment it wavered, looking to the West; but out of the West came a cold wind, and it bent away, and with a sigh dissolved into nothing.

Isso é quase idêntico ao que acontece com Sauron :

'The realm of Sauron is ended!' said Gandalf. 'The Ring-bearer has fulfilled his Quest.' And as the Captains gazed south to the Land of Mordor, it seemed to them that, black against the pall of cloud, there rose a huge shape of shadow, impenetrable, lightning-crowned, filling all the sky. Enormous it reared above the world, and stretched out towards them a vast threatening hand, terrible but impotent: for even as it leaned over them, a great wind took it, and it was all blown away, and passed; and then a hush fell.

Do que Gandalf disse sobre a destruição de Sauron:

For he will lose the best part of the strength that was native to him in his beginning, and all that was made or begun with that power will crumble, and he will be maimed for ever, becoming a mere spirit of malice that gnaws itself in the shadows, but cannot again grow or take shape.

Podemos estar quase certos de que Saruman sofreu o mesmo destino.

Existem 5 magos imortais Radagast The Brown, Gandalf O Cinza / Branco, Saruman O Branco, Morinehtar O Azul, e Rómestámo O Azul. Quando Durins Bane matou Gandalf nas minas de Moria, ele ressuscitou a si mesmo. Isso significa que os outros magos podem fazer isso. Se Saruman se ressuscitou, o que ele faria? Volte para Isengard com Ents ainda por aí? Eu não acho que Sauron não iria mais com ele.