On his blog today, Wez Furlong has release information about the latest release candidate of the PDO libraries - version 1.0RC2.

I released the next release candidate for PDO tonight. You can find the full changelog here. There are two changes of note:

• Changed PDO_XXX constant names into PDO::XXX and renamed pdo_drivers() to PDO::getAvailableDrivers()
• Removed the "final" attribute from the PDO and PDOStatement constructors, making it significantly easier to extend PDO in your apps.

You can grab the latest updates for this release canidate from the PECL repository or, if you're looking for the Windows side of things, the precompiled binaries are here...