Shameless plug: I recently wrote a Ruby gem to get/post Wikipedia articles from the command line. Then I can use my text editor to edit the articles which is faster than doing so in the browser. To install it: gem install wikian. To see how it works visit https://rubygems.org/gems/wikian.
I use Vim. Thanks for mentioning edit conflicts, I had overlooked that important feature. Will add it to the next version of Wikian by comparing timestamps of the local and most recent revisions.
