According to Evil Avatar, a fan-made map that recreates the Crossroads Mall from the Dawn of the Dead remake will be making it into Left 4 Dead in an update as Dead Before Dawn.
Here is a quote from the Left 4 Dead Mods forum (forums were down for maintenance when I tried to go) grabbed through Evil Avatar:
Dead Before Dawn, the replica of the Crossroads Mall from the movie Dawn of the Dead (2004) is coming to Left 4 Dead. The DBD team has been working tirelessly on the campaign and has vowed not to stop until the campaign is ready for release. Previously, we stated that the estimated release date will be the 1th of July (lol). At the time of this announcement, Valve was said to release the full SDK in a week’s time. That didn’t happen and we were forced to postpone the release date, BUT, Valve has now confirmed that next week we will have our dirty paws on the full version of the SDK and we’re ready for it. I would like to use this opportunity to give you guys a rundown of what’s been happening the past few months. So let’s get crackin’
Ok as you all (should) know, the Crossroads Mall map was originally made for the Half-Life 2 Mod, No More Room in Hell. Which is back into production and for the past 8 weeks, we’ve had regular updates from the mod team and they are hard at work. We cover all the news from No More Room in Hell on our site as well. (Since it’s Zombie related).
Myself and Darth_Brush are project lead on Dead Before Dawn (darth_brush being the godly mapper and I use my super powers in public relations and publicity to promote the campaign and various other tasks concerned to the campaign).
Video of the map: YouTube