Specifically:
BUGFIX: IDAPython's choose.choose() was broken.
BUGFIX: calling idaapi.del_hotkey() twice with the same argument could crash IDA.
BUGFIX: IDAPython's IDC emulation of idc.GetTevRegMem() was not working.
BUGFIX: IDAPython: execute_ui_requests() could crash IDA.
BUGFIX: IDAPython: IDP_Hooks instances could prevent the decompiler from working properly