I've created a workflow (with three actions) for creating new OmniFocus tasks.
One option simply creates a new task in the inbox based on the argument supplied
Another option creates a new task based on the currently-focused Google Chrome tab (the page title becomes the task name; the page URL becomes the note)
The third option creates a new task based on the currently-focused Safari tab (the page title becomes the task name; the page URL becomes the note)
Read a bit more on my blog, or download the workflow with this link:
https://www.dropbox.com/s/nlx4uyfc905iyc2/CreateOmniFocusTasks.alfredworkflow