So what I'm really curious about with DNF is what actually changed when Triptych took over development? According to the amazing Duke Nukem Forever musueum:
2009: In January, George Broussard says: Game developers often say "Cutting is shipping". We begin this year with a vengeance and a chainsaw. This means that he decided to scrap everything from the Duke Nukem Forever world chart that wasn't playable at a reasonable frame rate on the Xbox 360. This would result in Duke Nukem Forever levels being rebuilt to be linear.
Months later we got the leaked screenshots (I'm guessing it was in May 2009) and it looks incredibly similar to the released product, just with some unused areas + some levels that became DLC. I'm assuming January 2009 is when they chopped up the game from the 2008 world chart and streamlined it into what it is today. However, a 2011 interview with Jay Brushwood conflicts with this. Jay stated that Triptych took half the game and chopped it up - but isn't that what 3D Realms did in early 2009?
We do know that all the writing/jokes was written by the Triptych crew, and what 3DR had in May 2009 probably didn't have much writing finished. Triptych and Piranha Games also worked on the multiplayer mode. Also, Triptych made Vegas in Ruins take place during the day. The only other differences I can think of is if the May 2009 version actually had bigger versions of the final game's levels.
Here's are some images about something odd I thought stuck out in the final game:
This blocked off area looked really unnatural:

Here's the blocked off part in the final game:

The 2009 screenshots gallery contains this:

The multiplayer map:

Two ships underneath the multiplayer map:

It seems like I'm really grasping at straws but this had me curious for many years. The forum post topic "Former 3D Realms Employee speaks out!" seen right here: https://forums.duke4...yee-speaks-out/
mentions that it was 3DR that chopped the game up to get it running on consoles.
tl;dr: What really changed after May 2009?