Bitcoin version 0.6.0 is now available for download at: http://sourceforge.net/projects/bitcoin/files/Bitcoin/bitcoin-0.6.0/test/
This release includes more than 20 language localizations. More translations are welcome; join the project at Transifex to help: https://www.transifex.net/projects/p/bitcoin/
Please report bugs using the issue tracker at github: https://github.com/bitcoin/bitcoin/issues
Project source code is hosted at github; we are no longer distributing .tar.gz files here, you can get them directly from github: https://github.com/bitcoin/bitcoin/tarball/v0.6.0 # .tar.gz https://github.com/bitcoin/bitcoin/zipball/v0.6.0 # .zip
For Ubuntu users, there is a ppa maintained by Matt Corallo which you can add to your system so that it will automatically keep bitcoin up-to-date. Just type sudo apt-add-repository ppa:bitcoin/bitcoin in your terminal, then install the bitcoin-qt package.
Shutting down while synchronizing with the network (downloading the blockchain) can take more than a minute, because database writes are queued to speed up download time.
NEW FEATURES SINCE BITCOIN VERSION 0.5
Initial network synchronization should be much faster (one or two hours on a typical machine instead of ten or more hours).
Backup Wallet menu option.
Bitcoin-Qt can display and save QR codes for sending and receiving addresses.
New context menu on addresses to copy/edit/delete them.
New Sign Message dialog that allows you to prove that you own a bitcoin address by creating a digital signature.
New wallets created with this version will use 33-byte 'compressed' public keys instead of 65-byte public keys, resulting in smaller transactions and less traffic on the bitcoin network. The shorter keys are already supported by the network but wallet.dat files containing short keys are not compatible with earlier versions of Bitcoin-Qt/bitcoind.
New command-line argument -blocknotify= that will spawn a shell process to run when a new block is accepted.
New command-line argument -splash=0 to disable Bitcoin-Qt's initial splash screen
validateaddress JSON-RPC api command output includes two new fields for addresses in the wallet: pubkey : hexadecimal public key iscompressed : true if pubkey is a short 33-byte key
New JSON-RPC api commands for dumping/importing private keys from the wallet (dumprivkey, importprivkey).
New JSON-RPC api command for getting information about blocks (getblock, getblockhash).
New JSON-RPC api command (getmininginfo) for getting extra information related to mining. The getinfo JSON-RPC command no longer includes mining-related information (generate/genproclimit/hashespersec).
BIP30 implemented (security fix for an attack involving duplicate "coinbase transactions").
The -nolisten, -noupnp and -nodnsseed command-line options were renamed to -listen, -upnp and -dnsseed, with a default value of 1. The old names are still supported for compatibility (so specifying -nolisten is automatically interpreted as -listen=0; every boolean argument can now be specified as either -foo or -nofoo).
The -noirc command-line options was renamed to -irc, with a default value of 0. Run -irc=1 to get the old behavior.
Three fill-up-available-memory denial-of-service attacks were fixed.
NOT YET IMPLEMENTED FEATURES
Support for clicking on bitcoin: URIs and opening/launching Bitcoin-Qt is available only on Linux, and only if you configure your desktop to launch Bitcoin-Qt. All platforms support dragging and dropping bitcoin: URIs onto the Bitcoin-Qt window to start payment.
PRELIMINARY SUPPORT FOR MULTISIGNATURE TRANSACTIONS
This release has preliminary support for multisignature transactions-- transactions that require authorization from more than one person or device before they will be accepted by the bitcoin network.
Prior to this release, multisignature transactions were considered 'non-standard' and were ignored; with this release multisignature transactions are considered standard and will start to be relayed and accepted into blocks.
It is expected that future releases of Bitcoin-Qt will support the creation of multisignature transactions, once enough of the network has upgraded so relaying and validating them is robust.
For this release, creation and testing of multisignature transactions is limited to the bitcoin test network using the "addmultisigaddress" JSON-RPC api call.
Short multisignature address support is included in this release, as specified in BIP 13 and BIP 16.