FYI, here is a change log between 20161228-1 and 20170402-3.
AROS ABIv0 20170402 changes:
Functionalities:
Align naming of graphic drivers and make them visible in SysExplorer (Kalamatee)
Query graphics driver for 3D subdriver (Kalamatee)
C library improvements (Mazze, Kalamatee)
Kernel ACPI support (Kalamatee)
SysMon listing tasks better (Kalamatee)
Kernel IO-APIC support (Kalamatee, Schulz)
Kernel interrupt support (Kalamatee, Schulz)
Kernel SMP support (Kalamatee, Schulz)
Kernel shutdown/reboot support (Kalamatee)
Kernel spinlock support (Kalamatee, Schulz)
Public locking mechanism support (Kalamatee, Schulz)
Kernel CPU cores control (Kalamatee, Schulz)
processor.resource improvements (Kalamatee, Schulz)
SMP-enabled Message Port handling (Kalamatee, Schulz)
Protect access to Exec resources (Kalamatee)
Better measurement of CPU usage (Schulz)
SysMon listing CPU usage better (Kalamatee)
Graph.mcc (Kalamatee)
picture.datatype DTM_Write support (Mazze)
vusbhci.device (DizzyOfCRN)
Kernel MSI interrupt support (Kalamatee)
List.mui improvements (Kalamatee)
ACPI button driver (Kalamatee)
PCI driver IRQ routing table (Kalamatee, Schulz, Neil)
64-bit support:
misc fixes (Kalamatee, Schulz)
ahi.device, ac97.audio, hdudio.audio 64-bit support (Kalamatee)
pciusb.device 64-bit support (Kalamatee)
ata.device 64-bit support (Schulz)
Updates:
Flexcat 2.18 (Mazze)
libz 1.2.11 (Mazze)
libjpeg 9b (Mazze)
libpng 1.6.28 (Mazze)
AROS build system (Kalamatee)
Icons (Paolone)
GCC-6.3.0 (patch file) (Kalamatee)
Fixes:
Corrected datatype descriptors (Neil, Mazze)
VGA driver (Kalamatee, Neil)
Documentation (Neil, Kalamatee)
X11 driver (deadwood)
MUI (o1i, Kalamatee)
Shell commands (Neil, Kalamatee, Mazze, Schulz)
dos.library (Kalamatee)
C:Decoration (Kalamatee)
Kernel (Kalamatee)
Catalogs (polluks, mmartinka, Kalamatee)
Mesa (Kalamatee, Neil)
emul-handler (Neil)
console.device (Schulz)
Intuition (Schulz, Neil)
Preferences (Neil, balaton)
kms.library (Kalamatee)
pciusb.device (Schulz)
C library (deadwood)
Kernel ACPI support (Neil)
Kernel interrupt support (Neil)
PCI driver (Neil)
Kernel IO-APIC support (Neil)
atheros5000.device (Neil)
Kernel shutdown/reboot support (Neil)
Windows-hosted booting (deadwood)