With this extension you can easily add new tasks to Wunderlist using Alfred. To use it you need to already have Alfred version 2 installed and you need to have a Powerpack.
And older version, which is still comaptible with Alfred version 1 can be downloaded at the end of this post.
Simply double click on the Wunderlist 2.alfredworkflow extension to install it. You need to use the newest beta version of Alfred to use this extension.
My extension is really easy to use. You just have to keystroke wl followed by the task you want to enter, hit the return key and the task will be added to you're active list in Wunderlist.
wl Clean my Desk
-> This adds a new task to your list using the name "Clean my Desk".