Quote from: Bitinvestor on May 28, 2012, 11:39:26 AM

* Only allow e-mail addresses to be registered as aliases and verify that the person who registers it has access to it. This can be automated like most mailing lists do. It is necessary to provide this basic level of security to prevent Bulanula from associating his wallet address with gavin@acm.org, for example.

If you want a feature to add existing email addresses and to ckeck if someone really owns it, you insert control and you want someone else to control a registered alias. This is not possible in namecoin because there is no central control (and it must be like that for security reasons !).
What you can do is :
- adding alias with .bit domains, for example : khal@dot-bit.bit or khal@tor.bit
- adding alias with a namecoin mark : khal25@namecoin, manu44@namecoin, khal25@alia
- adding alias without domains : khal25, manu44

Quote from: Bitinvestor on May 28, 2012, 11:39:26 AM

* Make it independent of any coin (except Namecoin, obviously). Leave it up to the user to decide which coins to use and provide a secure data structure that any coin (existing or yet to be invented) can query to associate an e-mail address with a wallet address. While this feature isn't implemented by other coins it should still be possible to query Namecoin manually to list all the addresses for gavin@acm.org so that the right one can be copied and pasted into the client.

This is the case. One registration allows you to associate any kind of data (bitcoin address, namecoin, msn/jabber/xmpp email, nickname, gpg key, website, etc) with a unique "word". See it as an identity manager.

Quote from: Bitinvestor on May 28, 2012, 11:39:26 AM

* Allow the aliases to be modified quickly in case somebody loses his wallet or changes his e-mail address. Also make sure that people get notified early on when it is necessary to renew their alias to keep it in the blockchain.

Namecoin works like bitcoin. If you loose your wallet, you loose your keys, you loose you alias (but you have the time to give another one to people you know before it expires. Somebody can still query you and send you bitcoin for example).
What you can do is send the private key/wallet somewhere : on you mail address for example :p

Quote from: Bitinvestor on May 28, 2012, 11:39:26 AM

Is this possible?

Not the way you imagine it, but yes, it is possible :p

I know it would be convenient to use existing emails addresses but it is only possible if 1 person control the system. Are you sure you really want 1 person controlling 10'000 bitcoin addresses ?