Baseline (Widescreen) Solution & Issues
There are no resolution options in the game currently. The game can be resized like any window to whatever size you desire. It is strictly Hor+, with a locked vertical FOV in all situations. The game can be forced to fullscreen (by pressing F11). The game automatically is set to your desktops current resolution by doing this.
HUD scales correctly to the sides/center of the screen (the only HUD element currently not centered is the "Minecraft Beta" watermark.)
Please excuse the odd resolutions, as stated before, there are no resolution options so I had to eyeball it.
Ultra/Super-Wide (21:9/32:9) Specific Solution & Issues
Eyefinity / Surround Specific Solution & Issues
4k UHD Specific Solution & Issues