Working through the day with iPAD : Refreshingly positive experience

I have been one of the early adopters of iPAD and as some label me another Apple fanboy. I am sure smitten by the Apple sleek design and polish. Anyhow after the initial excitement had faded, my iPAD was becoming yet another gadget gathering dust other than the occasional desire to read my books on the iBook application. But two days ago, I said let me run with not taking my laptop of my backpack and work through the day with an iPAD. I had this twelve south company compass mobile stand which I neatly placed on my desk and start plugging in. I made sure, I had my read my emails and responded to the ones that needed a follow up or an immediate action. It was a breeze with every minute of my usage improving my typing efficiency. I had to read some RFP documents (typically 100+ page document PDF's) and I was able to open that quickly in the Good Reader application, annotate it and take my notes using the just released multi tasking feature. Out went my follow up email from my notes application. It was a simply a cool feeling. I then plugged on the Pandora online radio and had the music running as I read through an awesome iPAD version of Washington Post. Battery was there throughout the day and I felt my investment in iPAD was not a sunk cost after all. . I have to admit, I did not do a lot of document writing even though I had the Pages and the KeyNote application on my iPAD. Please feel share with your experience of using iPAD in a true productive setting.