http://www.comingsoon.net

Based on comments on his Official Website, it appears that Christopher Lee may indeed be in talks with Warner Bros. for the role of Dumbledore:

Sorry to change the content of this news. Mr Lee has not received official confirmation from Warner Bros and until then, we cannot confirm or comment any further.

Obviously it would be wonderful news and Mr Lee is overwhelmed, but for the time being nothing is certain.
http://www.thesun.co.uk/article/0,,2-2002500845,00.html

ACTOR Christopher Lee is tipped to take over Richard Harris’s role of Professor Dumbledore in the Harry Potter films.

The Dracula star, 80, is a “strong favourite” to replace Harris — who died last Friday aged 72.

Executives said Lee — a Bond villain in The Man With The Golden Gun — “fits the bill of Dumbledore perfectly”.

Lee was originally asked to be Dumbledore but refused because he was too busy.

Harris stand-in Harry Robinson is also in the running to land the role for the third film Prisoner of Azkaban, filmed next spring. Warner Bros will make an announcement this weekend.

wow and he is already 80