Thank you for writing this. I have been meaning to write this same sentiment on the forumns for weeks now and you have done a better job than I ever would have, thank you.
I am more extreme in my use of tags than many as I have over 1500 notes and have only one notebook. Tagging is everything for me and having this feature added would be a huge boost to my productivity with the iPad. My work flow on the desktop and iPhone uses the exact mechanisms listed above to be productive and this is definitely needed on the iPad. This feature would be higher on my list than any other feature that I would like to see.
Thanks again for calling attention to this very beneficial feature to a great product.