I have been using the Mac version of this application for as long as I have been using Mac, mainly for creating wireframes and visual notes. It costs five times more compared to iMockups, but consider the additional features and more importantly — the seamless integration with Mac version of the app, I will not hesitate to grab a copy of this too!
Additional note: Apples has announced on May 7, that iPad will be made available in nine more countries, namely Australia, Canada, France, Germany, Italy, Japan, Spain, Switzerland and the UK, starting from May 28. And what do you know, I’ll be visiting Vancouver for a month-long holiday with my wife, and my sister-in-law (who lives there) was sweet to have helped me placed a pre-order. It is scheduled to be shipped by June 7. Now I can only hope there will be no delay.