Yeah, SoftwareValet 2 with pkg support would be cool.
Unfortunately, doing a packaging system like SoftwareValet’s would involve a lot of time and reverse engineering. It would appear that YT has no intention of making it available to Haiku or anyone else. This may be a matter of “can’t” and not “won’t” because back in the day Be bought a company to get it. No matter, though. There are plans in the works already to set up a packaging system which will be even neater than SV. 
cool, but the easy way from SV must be implemented too 
The mac .pkg and installer system is nice. Streamlined, and effective. It runs post and preinstall scripts and has support to run system maintenance at install time (it "optimizes" the disk and updates prebindings) Making a Haiku installer that works similarly would not be difficult - especially if the focus was not dependencies and *nix mumbo jumbo - but a truly user os with each package either having everything you need, or not (in which case the developer is at fault or should provide links to other nessecary packages.
I have a strong suspicion that bs0 meant the BeOS Software Valet “pkg” system and not the OS X “pkg” system, but as they’re almost identical in how they operate to the user, its much of a muchness…
MYOB wrote:
I have a strong suspicion that bs0 meant the BeOS Software Valet "pkg" system and not the OS X "pkg" system, but as they're almost identical in how they operate to the user, its much of a muchness...
I got that. I am saying that recreating a system like Installer.app would not be extraordinarily difficult. Its just a package, an archive, a package list, a post-install script, and a liscence aggreement. THe installer reads, decomresses runs the script and then (in the case of os x) performs system maintenance tasks.