InstallerApps claim they have a leaked version of Installer 4.0 and have posted links to it.
Recently RiP Dev distributed the first beta of Installer 4.0 to established repositories in order to help them prepare their repos. Unfortunately, it seems someone has leaked this unfinished version out into the wild.
Please note before you attempt to install that you may experience crashes and/or bugs. This version was not intended for anything other then developer use.
On a side note, Rip Dev knows who leaked it. All beta's distributed to the ones that got accepted had a water mark on it. In fact, they know 99% who did it. And no, it was not iClarified :)