I just tagged the git tree "v0.5.0rc1". If you are able, please compile and help test.
See the INSTALL file at the top of the source tree for instructions on compiling. Binary releases for at least unix and mac should be available in the next day or two (there is a show-stopper bug on Windows, and we could use help from people familiar with cross-compiling using mingw to update the Windows build process).
Major bugs you should be aware of:
Wallet does not relock on Win32
Major changes from version 0.4:
Switched from wxWidgets for the GUI to Qt, using Wladimir J. van der Laan's bitcoin-qt. Why? We didn't have any wxWidgets programmers contributing fixes or improvements.
New JSON-RPC commands:
getmemorypool : alternative to 'getwork' that provides everything needed to construct a block with a custom generation transaction.
listsinceblock : Get all transactions in blocks since block [blockid]
signmessage/verifymessage : sign/verify a message with a wallet public/private keypair
Deprecated JSON-RPC features:
'midstate' data item from getwork requests
Deprecated JSON-RPC commands that have been REMOVED:
setlabel
getlabel
getaddressesbylabel
getamountreceived
getallreceived
getreceivedbylabel
listreceivedbylabel
Run: git shortlog --no-merges v0.4.0..
... to get a complete list of changes, and thanks to everybody who is contributing!