Mercurial 2.9 发布，此版本是普通发布日程的版本，更新内容如下：
aliases: make "_checkshellalias()" invoke "findcmd()" with "strict=True"
backout: add a message after backout that need manual commit
backout: avoid update on simple case
bash_completion: add completion for deleting a shelve
bash_completion: add global support for -B|--bookmark
bash_completion: add global support for -b|--branch
bisect: --command without --noupdate should flag the parent rev it tested
bookmarks: allow push -B to create a new remote head (issue2372)
branchmap: cache open/closed branch head information
cat: increase perf when catting single files
changectx: increase perf of walk function
clone: do not turn hidden changeset public on publishing clone (issue3935)
convert: use branchmap to change default branch in destination (issue3469)
date: allow %z in format (issue4040)
diff: search beyond ancestor when detecting renames
hgweb: infinite scroll support for coal, gitweb, and monoblue styles
merge: consider successor changesets for a bare update
patch: add support for git delta hunks
phase: properly compute ancestors of --rev on push (issue3786)
rebase: abort cleanly when we encounter a damaged rebasestate (issue4155)
rebase: do not crash in panic when cwd disapear in the process (issue4121)
record: --user/-u now works with record when ui.username not set (issue3857)
record: re-enable whitespace-ignoring options
relink: abort earlier when on different devices (issue3916)
strip: add faster revlog strip computation
subrepo: check phase of state in each subrepositories before committing
subrepo: make it possible to update to hidden subrepo revisions
subsettable: move from repoview to branchmap, the only place it's used
templater: selecting a style with no templates does not crash (issue4140)
update: consider successor changesets when moving active bookmark
url: added authuri when login information is requested (issue3209)
Mercurial 是一种轻量级分布式版本控制系统，采用 Python 语言实现，易于学习和使用，扩展性强。相对于传统的版本控制，具有如下优点：
更轻松的管理。
传统的版本控制系统使用集中式的 repository，一些和 repository相关的管理就只能由管理员一个人进行。由于采用了分布式的模型，Mercurial 中就没有这样的困扰，每个用户管理自己的 repository，管理员只需协调同步这些repository。
更健壮的系统。
分布式系统比集中式的单服务器系统更健壮，单服务器系统一旦服务器出现问题整个系统就不能运行了，分布式系统通常不会因为一两个节点而受到影响。
对网络的依赖性更低。
由于同步可以放在任意时刻进行，Mercurial 甚至可以离线进行管理，只需在有网络连接时同步。
项目主页：http://mercurial.selenic.com/
下载地址：http://mercurial.selenic.com/wiki/Download
来自:开源中国社区
