I've had the Kindle for over a year and the iPad for a few months now. Here's how I am using both devices.
In the video, I explain:
Reading fiction. Pretty much only on the Kindle device or on the Kindle app on the iPad/iPhone. I am quite loyal to the Amazon.com brand and experience as I have been buying physical books from overseas for years. It is a natural extension to move to the Kindle store, buy books there and read over multiple devices. The iBookstore is not very well populated as yet, and the Kindle app on the iPad is preferable.
Reading blogs. I use the iPad to relax and browse my Google Reader feeds as well as my social networks. I love using Flipboard, a fantastic app that formats the feeds into a magazine style layout with different sizes and pictures. It is addictive to read on Flipboard so that is how I find all the interesting articles that I tweet @thecreativepenn
Reading non-fiction/online course materials generally in PDF format. I do a lot of online courses and learning. Much of that material is formatted in PDF. I use GoodReader app on the iPad for this and love to be in the hammock with the iPad, a notebook and a cup of tea.
Multi-media. I am watching more videos on YouTube on the iPad as part of my surfing. I have also read some ebooks with embedded links to video that are great on the iPad specifically.
Traveling. When I was in Bali, I used the iPad for email, skype phone calls and twitter/facebook while I was away. I didn't take the Kindle device as it is specialized but I did sync the same books and read them on the Kindle app. Using the iPad for skype saved me lots of money on international phone calls as well as being easy for email so I could work seamlessly while traveling. It's definitely the device I will use in the future for travel.
Email/social networking/news on a casual basis. This may freak some people out but I often read email/twitter/FB/news while having breakfast! My husband also has an iPad and consumes different media to me. I often read UK and European news and he reads information from New Zealand (our respective countries of origin). Sitting at breakfast with a newspaper is not unusual for many couples, and for us, it is sitting with iPads. I don't feel like it is work when I can just check a few things on email, reply to a few tweets and catch up on the news.
Overall, the iPad replaces laptop usage rather than Kindle usage. I am shifting consumption of blogs/video/learning onto the iPad whereas I did that with my laptop before. It is much more relaxing to sit with the iPad on the couch than to sit with a laptop. I still use the Kindle device for reading fiction primarily as their are no distractions when using it. The iPad has multiple distractions!
Do you have an iPad? How do you use yours?