ZDoom 2.5.0 has been released.

The primary motivation for this release was the new vastly improved polyobject support. To recap, polyobjects in Hexen and previous versions of ZDoom had to obey these restrictions:
They had to be simple, convex objects.
They could not leave the subsector they were spawned in.
You could not have more than one polyobject per subsector.
None of these restrictions apply anymore:
Polyobjects can be any crazy shape you want.
Polyobjects can move anywhere on the map without restriction.
You can have as many polyobjects in a subsector as you want. You can even have polyobjects inside polyobjects if you feel like it!
You can also have a polyobject cover as many subsectors as you want.
There are some other improvements as well, including:
Support for uncompressed extended nodes, also supported by Eternity Engine and PrBoom+, to create a new cross-port standard for node storage.
Support for using Byte Map Fonts.
Ability to use metadata tags in audio formats to define custom loop points.
Added support for the MUSINFO lump (from Risen3D and PrBoom+).
Improved compatibility settings to optionally allow a greater faithfulness to the vanilla Doom and vanilla Heretic.
ZMAPINFO as an alias for MAPINFO to avoid compatibility problems with other ports parsing this lump.
Full rewrite of the SBARINFO system allowing many additional features and options.
Added support for multi-monitor display.
Buddha mode (one undestructable hitpoint)
Default reverb environment setting in MAPINFO
Several generalized codepointers to emulate some very specific Heretic and Hexen action functions
Enhanced poison damage system
Generalized railgun codepointers
New automap options
HOM detection system
...and more
There were some bugs fixed in there, too.