The latest stable release of the PEAR installer, version 1.4.9, has been released at pear.php.net. This release addresses a critical bug introduced in the release of PEAR 1.4.8 earlier this month. This version has been rigorously tested to ensure no future breakage (the last release had inordinate time pressure due to external circumstances). You can read about it and retrieve it at http://pear.php.net/PEAR.
Also mentioned in the post is their embarking on the next leap in PEAR's evolution - version 1.5.0. It won't be a major leap up (like from 1.3.x to 1.4.x), but many changes will be made - including extensive work on how PECL extensions are installed and implemented.