My apologies for the capitalised 'w', that was a simple mistake. I wouldn't go so far as to say it completely contradicts the 'feel', especially since australian (uncapitalised) will operate as a hybrid full service / low cost carrier. I continue to use that font in particular because I think it correctly conveys that theme; modern, clean, simple - everything australian intends to be.
.... also, I couldn't find one I liked better ( ), and by using the font again, i'm maintaining some level of consistency across my australian branding
Edit: For reference, other fonts I've used for my australian branding can be seen on the 'Its how we fly' livery, towards the top of this page, and the Club Australia cards on the previous page of this showcase. The font used in the above billboards is that used for my Ocean Card and Australian Express/World branding items, which are also located on the previous page.