They offer a variety of short walking tours, hiking tours off the beaten track and sightseeing strolls in the beautiful city of Vienna. These walks are published in their books, and some of them also on their website. Check it out for more information.
Seems like they already do cover a lot of what my walkability concept is about, and they do it really well. So the question for me is - does Vienna need my "walkability"? For now I have set my goal in researching the existing companies and communities and am happy to just blog a bit on my website. We'll see if there is a little niche for my walking business. I'm in no hurry.