Alright so a new video came out came out of how Roblox reached 200,000 Parts, to start off the bricks have to load via a script, Roblox's current way of loading the bricks would just crash the game, meaning loading is slow.
http://www.youtube.com/watch?feature=player_embedded&v=6XkkVZKHKJg
However, looking at the style of the map and looking at some parts of the map, I can almost SWEAR this is Badspot's Block Party possibly mixed with some other Roblox builds. Look at 0:09 at the right and it looks like that gate thats in the Block Party!!
EDIT:There is a way to convert BL saves into Roblox bricks as I have gotten some done by the user HatHelper, thats how I made my "Roblox vs Blockland brick loading". The user HatHelper must have gave this to devs or did a conversion of the map and the devs used it.
EDIT:I was right! The link in the video to the place is by HatHelper, he must have converted the save! http://[]www.roblox[.]com/Large-Place-place?id=83305737
Remove the []
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