Have you ever thought of the possibilites that satoshi wish to stay anonimous becayse he doesnt want people to know who he is because he might be a celebrity and alot of countries will be pursuing him in attempt to make him work for the country? Satoshi could be the quiet guy that doesnt need any fame at all and no there is no proof that he is dead already
Where is your proof that he is alive?
Well not much proof exists either way, the message satoshi sent revealing to us he is not Dorian Nakamoto on GMX.com, could be considered a sign that he is alive. Granted he should have signed the message to give us more validation. More likely than him being dead is he is just involved with other research topics currently, satoshi was well aware of the 'hornets nest' before/during/after Bitcoin was introduced to the public. Satoshi's entrance, existence and exit in the community were all carefully planned out ahead of time.
Also for those thinking that satoshi 'lost' his private keys... stop kidding yourself. If someone architects a system reliant on asymmetric cryptography, how could they ever forget to save the KeyPairs...never would that happen.
Not when his email account was hacked and a random hacker has sent this message, like in this case...