I just received word fom Roel Spruit, the guy behind BlenderArtists, that the website is currently down for maintenance. Roel is performing an upgrade that takes longer than expected. The site should be back online by tomorrow.
I have a LONG history with Blender - I wrote some of the earliest Blender tutorials, worked for Not a Number and helped run the crowdfunding campaign that open sourced Blender (the first one on the internet!). I founded BlenderNation in 2006 and have been editing it every single day since then ;-) I also run the Blender Artists forum and I'm Head of Community at Sketchfab.