Update:I have received several messages asking about how to redeem (import) in Blockchain.info (using a new wallet since legacy is no problem). This post is to give the quickest way to accomplish this as there are several ways and then supporting information.
The key under the label (like Casascius) is a 'Mini Private Key'. (So, this method is the same for Casascius coins and others).
In my case, this is: SqtVvMgDxWyXMrAdas7PirKQp7YbMz
Step 1 - Convert your mini-private-key to an 'uncompressed private key'
www.bitaddress.org (Use offline version for safety)
Click on 'Wallet Details' (You don't have to wait for a random wallet to be created)
Copy in your mini key - example: SqtVvMgDxWyXMrAdas7PirKQp7YbMz
Then click 'View Details'
Copy out the Private Key - example: 5Jkp75Gb3jRLTF7rXJvXJNuM7t1QbX2muMJUh8Pa56qxpaREuck
Step 2 - Blockchain.info
Create a new wallet or use an already made account.
Go to 'Settings', then 'Addresses'
Click on 'Import Address'
Paste in your private key - example: 5Jkp75Gb3jRLTF7rXJvXJNuM7t1QbX2muMJUh8Pa56qxpaREuck
The above is all you need to do.
It's that simple. of course, you should either move the coins to a more secure address if you want, and then delete the address from your wallet should you choose.
Now for details / issues....
A 'Mini Private Key' can be easily converted to:
wif (compressed): L1NNuoqoH4EQrqKFan7Ejhg3oN8o9MYqC4c9E7ccy6o7Nk9wtU9w
uncompressed: 5Jkp75Gb3jRLTF7rXJvXJNuM7t1QbX2muMJUh8Pa56qxpaREuck
In turn, they are:
Bitcoin address: 1CCUSKpW6ZNRCYCTurAg3XU8afbk9p9yqx
Bitcoin address uncompressed : 1BaTSwatnqGKsuhfZQYsy4kAgAMfV2g7Kb
Blockchain.info legacy (old wallet) works with the 'Mini Private Key' in that it will import the uncompressed Bitcoin address which is used for coins.
The new wallet, although appears to work, it converts the 'mini-private-key' to wif (compressed) private key and then uses the compressed bitcoin address.
New Wallet: SqtVvMgDxWyXMrAdas7PirKQp7YbMz --> L1NNuoqoH4EQrqKFan7Ejhg3oN8o9MYqC4c9E7ccy6o7Nk9wtU9w --> 1CCUSKpW6ZNRCYCTurAg3XU8afbk9p9yqx
Old Wallet: SqtVvMgDxWyXMrAdas7PirKQp7YbMz --> 5Jkp75Gb3jRLTF7rXJvXJNuM7t1QbX2muMJUh8Pa56qxpaREuck --> 1BaTSwatnqGKsuhfZQYsy4kAgAMfV2g7Kb
I don't know why Blockchain.info made this change. This is scary for the person first trying to import/redeem as it appears the bitcoin address on the label doesn't match the private key. And, google doesn't have results for the difference between Old and New blockchain.info wallets. Also, blockchain.info doesn't have any supporting information in their help/faq regarding this difference.
Another thing that is a shame is that you can't simply 'sweep' an address in the 'New Wallet' format which you could have in the 'Old Wallet' (legacy) format.