It would be used by anyone that wants to store their private keys offline, but still manage their wallet on an offline computer.  This does include companies.

The company would have a secure office somewhere with a non-internet-connected computer.  They would create one wallet per cash register, and the copy the watching-only version to each register.  Then the registers could monitor transactions, and generate addresses for customers, but the register would not be able to spend any of the money.

Then if the company wants to move the cash, they can create the transaction from the register, but the txs can't be signed.  Instead they are copied to a USB key, taken to the secure location, and the offline system signs all of them.  The final transactions are taken back to the internet and broadcast.

But this is useful for anyone who wants top-notch security.  If I have more than $100 in BTC, I'll be keeping it in a wallet that has never touched the internet.  By using this feature, it is virtually impossible for an attacker to compromise your keys, because the private keys have never left the offline computer.  Some creative USB key viruses might succeed, but that's a big stretch, requiring a very specific, targeted virus -- and if you're concerned about that, you can do something creative using the raw transaction blocks of text (perhaps convert them to QR code and scan from the offline computer?  then you never even plug in a USB key).

The community here has come up with all sorts of command-line tools for doing this, but they are all complicated and pretty much only accessible to the die-hards.   I believe that Armory will bring this functionality to anyone who wants to use it, and they might even figure it out without a tutorial!  If that works, then I've succeeded!  (btw, you can add donations to offline transactions the same as online transactions )


EDIT:  to answer one of your questions more directly.... wallets are never copied/moved after the initial distribution.  Once they are in place, the only thing that is moved/copied between systems is transaction files (*.unsigned.tx and *.signed.tx).  In fact, the offline computer doesn't even need the blockchain!  That's innovation!   (the other solutions I mentioned above which are complicated, do require making sure the offline computer maintains a sync'd blockchain)

PLEASE DONATE.  This was a TON of work, and I'm not sure I can continue neglecting my girlfriend without getting some kind of compensation for the development time.  Please use the "Donate" button on the send-bitcoins dialog in Armory.  Here's the address if you are feeling generous without using the program 1Gffm7LKXcNFPrtxy6yF4JBoe5rVka4sn1

  Too bad you arn't recording all the frustration and anguish of getting this thing wrapped up. You could release that footage to entertain while we wait. 

Well -- it's gone pretty well except for the gift pickups. We've got about 160 BTC in outstanding gifts that emails were sent to, but who haven't managed to get their gifts. [edit: Meaning, they haven't downloaded MultiBit or another client and actually claimed them]. I ran a bunch of gifts out myself on Christmas Eve, so I know we weren't getting spam boxed -- so if anyone who used the service hasn't had a note saying their friends picked up the gift, email them and help them out!

A month from now, we're going to send out notices to the senders of any unclaimed gifts, giving them an address to pick up the coins; and March 1st, whatever's leftover will be donated to Habitat for Humanity.

All in all, we regard it as a success... it brought some good attention to the community, and got some new people involved.

Okay guys. This baby is crowning.

Final encoding and it'll be off to furryredtube.

i was going to write a retort to this article, but the whole thing was so ludicrous i couldn't think how to respond

http://www.kernelmag.com/yiannopoulos/2011/12/the-online-currency-wars-are-coming/

"Since Bitcoin has no central repository it’s more like digital cash, used to exchange value anonymously. Critics ask how long that anonymity will last."

what the hell does that mean.

"Think of the entire internet as an app, circumscribed by a persistent Facebook login and punctuated with Pay icons"

No.. that's just stupid.

"Bitcoin and Ven haven’t even scratched the surface of what’s possible with online payments. With a ready user base of 800 million users, Facebook may be about to change the way online financial transactions are thought about and conducted. "

yeah right. bitcoin underlying protocol can do shit we havent even dreamed or ever thought possible. sky is the limit!

Well here is the update;  http://ericolson2012.com/2011/12/149/

My announcement, just posted up on Facebook and Google +.  Website is pretty sparse still, but compared to my opponents I think I actually have more issue related information.  Sadly...  They have pictures, I'm working on that still..

Not much in the way of promotion yet.  Sometime between Xmas and New Years, there will be some media presence.  Though my primary goal at the moment is getting ballot access.  Things are falling together.