My Kindle was bought for reading books rather than as a general purpose mobile Internet device. Therefore, my use of these features is related to the primary purpose.
- Browser: I played with the experimental browser for a bit but felt it was so crippled that I wasn't interested in playing further. As more and more sites develop "mobile" web presentation, I might revisit this in the future. Since I'm on my laptop most of the time and have an air card, I can get online with a full-function browser rather than having to resort to the primitive one built into the Kindle.
- Browser exception: I use the catalogs (officially called download guides) from Feedbooks and MobileRead. These books use the underlying browser to allow you to download a MobiPocket-formatted book directly to the Kindle or to download a more recent version of the guide.
- Amazon store: I use the Whispernet connection to visit the Amazon store every couple of days. I check out the Kindle Daily Post, reading back to the last time I looked, to see if any free or deeply discounted deals have been announced. I tend to "buy" and select samples from my PC, so when I turn on the Whispernet connection, that content is transmitted to my Kindle. I download Amazon books to the PC when I'm outside of the US and need to use the fall-back process of transferring books through the PC.
- Highlighting: All the time. I've been collecting some documentation for feedback on poorly built books -- particularly formatting problems in those in "Topaz" format.
- Notes: on occasion. A neat trick is that you can open the "My Clippings" book and add a note in it, which gives you an easy notepad or piece of scratch paper to scribble a note on -- which is related to no book at all.
- Dictionary: infrequently. But I haven't figured out how to go from entry to entry in the dictionary, which is a way I like to use the dictionary.
- Search Wikipedia: infrequently. It's easier to do that with my PC and since I keep the antenna turned off most of the time, it's more of a nuisance to have have to turn it on to run the search.
In summary, I like having the easy network access -- without even having to log into a WiFi network -- for downloading books. It's not required, but it's convenient.
I could be happy with a Sony or other eBook reader that doesn't have the network capability -- as long as I had the Amazon store available. IMNSHO: One of the best things Amazon could do would be to set up additional stores for BBeB, MobiPocket, and ePub books and maybe others. And other online bookstores could do something similar. Then regardless of which device you owned, you could shop at your favorite online book seller. I'd like to see it possible for other sellers to offer Kindle-specific formats. Amazon could restrict direct delivery from other sellers if they wanted, positioning the Amazon Kindle and the Amazon Store as the best combination, but allowing customers to choose their device and supplier.