No. The moment right now running gives the error:

# guix pull
Updating channel 'guix' from Git repository at 'https://git.savannah.gnu.org/git/guix.git'...
Building from this channel:
  guix      https://git.savannah.gnu.org/git/guix.git    ad8a4a6
substituting /gnu/store/9acqfn7g6nfgvcrzkq84dlc69ps8b2vg-git-2.19.2.tar.xz...
guix substitute: error: connect: Connection timed out
substitution of /gnu/store/9acqfn7g6nfgvcrzkq84dlc69ps8b2vg-git-2.19.2.tar.xz failed
guix pull: error: build failed: some substitutes for the outputs of derivation `/gnu/store/c1mzmfkmxcimgyq0322bx3044qi1llqi-git-2.19.2.tar.xz.drv' failed (usually happens due to networking issues); try `--fallback' to build derivation from source

Berlin works:
# guix pull --substitute-urls=https://berlin.guixsd.org
Updating channel 'guix' from Git repository at 'https://git.savannah.gnu.org/git/guix.git'...
Building from this channel:
  guix      https://git.savannah.gnu.org/git/guix.git    ad8a4a6
updating substitutes from 'https://berlin.guixsd.org'... 100.0%
updating substitutes from 'https://berlin.guixsd.org'... 100.0%
Computing Guix derivation for 'x86_64-linux'... |
nothing to be done


# traceroute hydra.gnu.org
traceroute to 20121227-hydra.gnu.org (18.4.89.46), 64 hops max
  1   x.x.x.x  1.567ms  0.801ms  0.752ms
  2   x.x.x.x  1.850ms  3.188ms  4.537ms
  3   x.x.x.x  6.246ms  8.411ms  6.997ms
  4   212.73.250.154  47.733ms  49.409ms  52.103ms
  5   *  *  *
  6   *  *  *
  7   4.53.48.98  160.639ms  161.683ms  161.171ms
  8   18.69.9.1  160.537ms  161.068ms  160.717ms
  9   18.69.1.2  157.535ms  157.356ms  156.771ms
 10   18.123.55.2  160.199ms  161.479ms  160.308ms
 11   18.4.89.21  158.786ms  158.635ms  161.484ms