Greg Beaver has a note over on his blog concerning the delay for PEAR 1.4.0a1, and the causes behind it.

There will be another delay to the release of PEAR 1.4.0a1, but this will be very short. The list of things that are completed that were not completed is so long, I won't even begin. The only items left to fix prior to release are: the problem I found in pear sign and, implementing the new pecl.php.net channel.

[...] That only leaves implementing a few tests for the new pecl migration stuff, trying to break it, and then releasing it. Thank you all for being so patient, it's been a long ride, but PEAR 1.4.0a1 will be far more stable than an initial alpha release should be, and as a result, PEAR 1.4.0 stable will arrive much sooner than it would otherwise have arrived.

Sounds like things are just about to wrap up on this distribution, so keep your eyes open and your code ready for the new upgrades...