Pacman 3.1.0 has been released to testing. It has been a long time coming, but a lot of work has been put into it by several contributors over the last 9 months.
Note that some options have changed so your scripts may be incompatible with the new version and will need some slight modifications. In addition, makepkg and pacman no longer require .FILELIST files in built packages, so any packages built with makepkg 3.1 will show a warning in pacman 3.0 about a missing filelist- this can be safely ignored.
Please report any bugs to the Pacman Project on Flyspray or by sending an email to the pacman-dev mailing list with as much information as possible. Please check to see if your problem has already been reported first!
Please see the pacman website for more information on what has changed since the 3.0.X releases.