There's a beta of 2.5.0 for Snow Leopard available at http://xquartz.macosforge.org/downloads/SL/XQuartz-2.5.0_beta1.dmg . It seems to work for me.

not for snow leopard, i think. later release will do.

OK, X11 2.4.0 will not be released for SnowLeopard. 2.4.1 will be the first release that can be installed on SnowLeopard. waiting...

Not for 10.6+ Snow Leopard

2.4 this is not for snow leopard

dingeruk below is incorrect about Snow Leopard releases:

"1.6 [sic] contains version 2.3.4 of X11. Not surprisingly, this version lies between 2.3.3.2 and 2.4.0. It contains all the fixes that went into Xplugin, quartz-wm, and most of the server fixes, but it is still on the 1.4 server branch. Most of the userland libraries were updated to what was shipped in 2.4.0 with a few exceptions.

2.4.0 will not be released for SnowLeopard. 2.4.1 will be the first release that can be installed on SnowLeopard. There will be separate Leopard and SnowLeopard packages for 2.4.1 and later. On SnowLeopard, X11 will no longer install over the system's X11. It will install in its own prefix to allow side-by-side use with the Apple-provided X11."

—from http://xquartz.macosforge.org/trac/wiki#SnowLeopardNotice

I prefer to avoid running applications that need X11, but it's worth it for certain gems like The GIMP. Apple has given us a really slick X Server that integrates seamlessly into the Mac OS X GUI. It even supports running some X applications that are being tunneled remotely via SSH!

2.4.4 is only for Leopard Users, 2.4 is the latest version for Snow Leopard

Version 2.3.3 seems to require 10.5.7

I get an error message saying something about insuficient information and to contact the developer. I think i'll just wait for the update in the Apple Updater.