I read a lot of pdfs that I've printed from websites, and like to make notes on them, and I've been VERY pleased with the recent update that lets you click a single button and turn a web page you're viewing on the LCD side into a pdf or epub document on the ereader side, which you can then save/annotate/whatever.

So if you're reading articles online and want a very easy way to not only read them, but convert them to pdf and store them, and also allow you to highlight, write notes, add text notes, then this is a great device for that. It's fine for pdfs that you already have on your computer, but the ability to convert on the fly from an open web page is really a stellar feature.