Current estimates give the IANA free pool until July of 2011. May 2012 for when the RIRs allocate their last addresses. The E blocks would likely only buy about an additional year. But, hey, what possible future use can they have if v4 goes away so why not use them now.

Actually, have you tried using a class E address? Not all that long ago, even Linux wouldn't permit use of a class E address, although it appears that has been fixed. Given the number of ancient installations of all sorts of operating systems out there, it would not surprise me to find that a non-trivial fraction of internet-facing devices would simply barf if assigned such an address or if instructed to access said address.

As another data point, pinging a class E address from a fully patched Windows XP machine says "Destination specified is invalid." which means Windows up to XP has class E blocked at the network stack level. That means Win2k and previous also have that problem.

Of course, that's not to say we shouldn't fix things so class E space can be used. After all, what's the point of not using it?

Bzzzt! Fail.

That only works on the *server* side. TFA is talking about the *client* software which saves the password for you so you don't have to enter it every time. There is no possible way for the client software to provide the correct password to the server unless it can obtain it, either by decrypting its stored password or by querying the user. So, no, a one-way hash is not usable in that circumstance.