The-Ctrl-Alt-Del.com has the latest leaked beta Detonator drivers, version 12.20, for Windows 2000, Windows NT 4.0, and Windows9x/Me. You can grab them here.
Some users are reporting marginally improved performance, while others have the opposite result. It appears that the main new feature is enhanced TwinView in Windows 2000: A new panel called 'Desktop Utilities' is said to appear, which "gives full TwinView control for apps, cross screen magnification, auto app window selection, all sorts of stuff that should have been in there already".
Note: These are beta drivers, so be careful.