What I expected to happen was...:
I expected to create a new world and have it load under normal conditions, as a world in older versions would.

What actually happened was...:
The world was created, it went to the default "dirt" loading background, flashed a "0%" on the top half of the screen, and then presented me with a blank world that I assume was "loading" itself. While it was loading, the game crashed to launcher.

Steps to Reproduce:
1. Create a new world.
2. Wait for load.
3. Game crash to launcher.

Error Log:
Completely ignored arguments: [--nativeLauncherVersion, 286]
[08:01:16] [Client thread/INFO]: Setting user: GoldenBucket
[08:01:16] [Client thread/INFO]: (Session ID is token:983fd082a3714147ade1e512a30bb0fa:05c496f587244eeeb9105ac6e922fca3)
[08:01:20] [Client thread/INFO]: LWJGL Version: 2.9.4
[08:01:21] [Client thread/INFO]: Reloading ResourceManager: Default
[08:01:22] [Client thread/WARN]: Missing sound for event: minecraft:entity.snowman.ambient
[08:01:22] [Sound Library Loader/INFO]: Starting up SoundSystem...
[08:01:22] [Thread-5/INFO]: Initializing LWJGL OpenAL
[08:01:22] [Thread-5/INFO]: (The LWJGL binding of OpenAL. For more information, see http://www.lwjgl.org)
[08:01:22] [Thread-5/INFO]: OpenAL initialized.
[08:01:22] [Sound Library Loader/INFO]: Sound engine started
[08:01:25] [Client thread/INFO]: Created: 1024x512 textures-atlas
[08:01:53] [Server thread/INFO]: Starting integrated minecraft server version 16w04a
[08:01:53] [Server thread/INFO]: Generating keypair
[08:01:56] [Server thread/INFO]: Preparing start region for level 0
[08:01:57] [Server thread/INFO]: Changing view distance to 12, from 10
[08:01:58] [Server thread/INFO]: GoldenBucket[local:E:187e1ee4] logged in with entity id 0 at (9.5, 4.0, -454.5)
[08:01:58] [Server thread/INFO]: GoldenBucket joined the game
[08:02:00] [Server thread/INFO]: Saving and pausing game...
[08:02:00] [Server thread/INFO]: Saving chunks for level 'Attempt 2 at 1.9 Snapshot'/Overworld
#

1. A fatal error has been detected by the Java Runtime Environment:
   #
2. EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x00007ffcc638628c, pid=10420, tid=10704
   #
3. JRE version: Java(TM) SE Runtime Environment (8.0_25-b18) (build 1.8.0_25-b18)
4. Java VM: Java HotSpot(TM) 64-Bit Server VM (25.25-b02 mixed mode windows-amd64 compressed oops)
5. Problematic frame:
6. C [ig75icd64.dll+0x55628c]
   #
7. Failed to write core dump. Minidumps are not enabled by default on client versions of Windows
   #
8. An error report file with more information is saved as:
9. D:\Games\.minecraft\hs_err_pid10420.log
   #
10. If you would like to submit a bug report, please visit:
11. http://bugreport.sun.com/bugreport/crash.jsp
12. The crash happened outside the Java Virtual Machine in native code.
13. See problematic frame for where to report the bug.
    #
    AL lib: (EE) alc_cleanup: 1 device not closed
    Java HotSpot(TM) 64-Bit Server VM warning: Using incremental CMS is deprecated and will likely be removed in a future release