user3047: I understand that addresses do not have to connect to the bitcoin network/blockchain in order to be valid addresses, but I am mainly wondering about what can be seen in the blockchain if that address has never connected to the network.
So given this scenario
AddressA sends 1 bitcoin to cold AddressB.  AddressB has never been online.
There will be a transaction id for this. But what would a site like blockchain.info show for the balance of AddressB?
Would it still be able to aggregate all of the transaction that go to AddressB to show a balance for AddressB?

user3171: Here's how I've been explaining it lately:
When you first generate a public/private keypair offline (or "cold"), obviously the blockchain knows nothing about it.
However, the first time someone (usually you) sends Bitcoin to your public key, the blockchain adds a column in its record-keeping ledger for your public key forever, and continues to track its balance, also forever.
The purpose of your private key is simply to prove that you have permission to send coins away from that address. It's a certificate of ownership, it says, "I made that public key, and here's my proof." You keep it secret because if someone else gets a copy of your certificate of ownership, they can spend your coins without restriction.
Does that make sense (or answer your question?)

user8966: There is no "being online" concept of an address in bitcoin. 
An analogy would be to think of bitcoin addresses as if they were an email addresses. You can send to that address whenever you want and only the person with the secret key will have access to the contents of it. It doesn't matter if they are 'online' or not.
So to answer your question, when you first generate an address only you will know about it (unless of course you share it somehow).
As soon as you or someone else sends bitcoins to that address it will be present in the blockchain as part of a transaction

3047: <p>I understand that addresses do not have to connect to the bitcoin network/blockchain in order to be valid addresses, but I am mainly wondering about what can be seen in the blockchain if that address has never connected to the network.</p>

<p>So given this scenario</p>

<p>AddressA sends 1 bitcoin to cold AddressB.  AddressB has never been online.</p>

<p>There will be a transaction id for this. But what would a site like blockchain.info show for the balance of AddressB?</p>

<p>Would it still be able to aggregate all of the transaction that go to AddressB to show a balance for AddressB?</p>
 3171: <p>Here's how I've been explaining it lately:</p>

<p>When you first generate a public/private keypair offline (or "cold"), obviously the blockchain knows nothing about it.</p>

<p>However, the first time someone (usually you) sends Bitcoin to your public key, the blockchain adds a column in its record-keeping ledger for your public key <em>forever</em>, and continues to track its balance, also <em>forever</em>.</p>

<p>The purpose of your private key is simply to prove that you have permission to send coins away from that address. It's a certificate of ownership, it says, "I made that public key, and here's my proof." You keep it secret because if someone else gets a copy of your certificate of ownership, they can spend your coins without restriction.</p>

<p>Does that make sense (or answer your question?)</p>
 8966: <p>There is no "being online" concept of an address in bitcoin. </p>

<p>An analogy would be to think of bitcoin addresses as if they were an email addresses. You can send to that address whenever you want and only the person with the secret key will have access to the contents of it. It doesn't matter if they are 'online' or not.</p>

<p>So to answer your question, when you first generate an address only you will know about it (unless of course you share it somehow).
As soon as you or someone else sends bitcoins to that address it will be present in the blockchain as part of a transaction</p>
