In addition to the @inkscapetuts on twitter, the inkscape tutorials blog is now also on google+, and also on Facebook. Going forward, both the twitter, g+ and Facebook streams will be updated with all the new posts that show up here on the blog. So if you prefer to use either of those services, follow us there.
Speaking of google+, there is also the official inkscape google+ page, which features news and updates from the inkscape project. Also, there is the inkscape community on google+, that has tutorials, a gallery, and general inkscape posts and discussions.