What do you guys feel is the best facebook clone script on Codecanyon today?
Search the marketplace for phpDolphin - definitely the best.
i had created a exact facebook clone built with pure php/mysqli/html5/css3 no framework
it has all the features of facebook and more but it was rejected on here as the theme was to much like facebook and others on here 
so im redesigning the theme
Front-End Features:
User Regestration
User Login
Profile
Profile Photo
Profile Cover
Add/Remove Friends
Live Chat
Wall
Photos
Ads
Groups
Tag friends in posts
plus more
Future Release Features:
Events Manager
Pages
Chat Bar
Backend Features:
Admin Dashboard for site overview
Update Notification
Add User
Remove User
Edit User
Ads Manager
Site Cache Settings
Site Basic Settings
Prerequisite:
PHP 5.3 OR >
MYSQL 5 OR >
APACHE
mod_rewrite
PHP Function curl
PHP GD Library
JSON Support
XML
Sounds good. Id like to see your work when it is ready.
it will be in stable version in about 1 month 
i dont know if it will every be available on here though
ive just added autocomplete for the location and @mention
it also as a system auto update in the admin area
its based on a friend system but soon will also have a follow system 
its got a new feature added block system and a user interaction system (poke, ect.)
many more features coming soon