I'm having difficulty with the Wi-Fi connection ... the router is way up in DH's office and I stay down in our basement most of the time, so I lose connection frequently.
Other than that, I like the iBook reader OK but prefer my Kindle. I'm a writer and I spend 8 hours a day on a computer. Looking at the backlit screen is hard on my eyes. The Kindle's matte screen and paper-like font and coloring are a bit easier to read.
Video is awesome and the apps are fantastic (although pricey). This is DH's test model for his work -- I've pre-ordered the 3G model for myself since I travel often.