I quite literally just purchased this app after seeing it on AppShopper this morning because I was wanting to use up some iTunes credit I had...
Now I'll try to provide a short review...
Impressions: First, let me say, this thing is great. I'm sitting here now working on a Word document and threw my formatting palette and my desktop Twitter client on my iPad's screen. There is a little bit of lag, but nothing that would ever make me regret this purchase. Not to mention, the resolution (for me at least) is more than adequate.
Limitations: Of course, one of the first things I pushed over to my second display was a video (Leo Laporte's Tech Guy video podcast), this is where I saw a small hiccup. The video was a bit choppy, not unwatchable, but then again, the video is just a guy sitting at a desk doing a radio show...that being said, I wouldn't want to throw any graphics intensive HD video over to it. Another limitation would be the sleep/auto-lock on my iPad. I found, after the five minute auto-lock feature was activated, that the display went to sleep and required a quick reconfigure. This issue was resolved by me just sitting my iPad to never auto-lock. This is just something I'll have to do when sitting at the desk working. Lastly, the touch screen is mapped to your mouse, so if you do feel the need to reach over and tap, for instance, a link in a Tweet, it will perform the same function as actually clicking with your cursor.
Setup: The setup is straight forward, and just as described on the App Store page. Upon downloading the actual app and a quick sync to get it over to my iPad, you launch the app and are instructed to go to the developer's site and download the Preference Pane. Now, for my particular configuration, I am using my MBP in clamshell mode hooked up to a 23" external monitor. Your display prefs. automatically detect it and you'll be off and running. This is seriously one of the easiest setups like this I have seen. In short, if you're comfortable with syncing documents/apps using iTunes to your iPad, you can do this.
Recommendation: If you spend any time at all in applications like the Office Suite, IM apps, Twitter clients, anything that has a palette or moveable toolbar, you should own this app. I already see it coming in handy while on extended trips, as some of us will have our Macbook and iPad in tow anyway, because who actually takes an external monitor with you everywhere you go?
