The first beta for the next major version of Freeciv, 2.5.0-beta1, has just been released.
2.5.x includes a version of bard's civ2civ3 ruleset as standard, and some AI improvements; apart from that there are relatively few changes for players, although there is a a lot of extra flexibility for authors of custom rulesets. See the summary of changes since 2.4.x.
Source code is available here. Compiled Windows packages aren't available yet, but will hopefully follow shortly.
Beta release 2.5.0-beta1
Re: Beta release 2.5.0-beta1
The Windows builds are now up; thanks to Christian as usual.