So with recent Mercurial 1.7 releases HTTPS support was tightened, so you are bound to encounter a warning in the form of: warning: bitbucket.org certificate not verified (check web.cacerts config setting).
Now, on http://mercurial.selenic.com/wiki/CACertificates there are details on what to configure for certain operating systems. Given I use FreeBSD, I altered my $HOME/.hgrc as follows:
[code]
[web]
cacerts = /etc/ssl/cert.pem
[/code]
For OpenBSD this should be in the same place since release 3.8. But apparently NetBSD does not have such a file in base.
For those who administrate a multi-user system: add the configuration text to /etc/mercurial/hgrc or as specified in http://www.freebsd.org/cgi/man.cgi?query=hgrc&manpath=FreeBSD+8.2-RELEASE+and+Ports . Thanks for the tip Jeroen. :)