PHP 5.5.0 alpha 1 was released a few days ago. New features include:
- support for Generators,
- a new password hashing API,
- support for finally in try/catch blocks,
- support for list() in foreach,
- constant array/string dereferencing,
- ext/intl improvement
More info on these features can be read in Test Drive PHP 5.5: A Sneak Peek and What PHP 5.5 might look like