Kindle for the Web makes it easier to access the content, but the real step forward here is the ability to embed the sample in another website. Here's that Step by Step book embedded in this blog post:
What a terrific way for authors and fans to showcase excerpts on their websites. Kudos to Amazon for offering this service, but I'd encourage them take it further. For example, let each person decide which portion of the book they want to excerpt. Yes, I know the danger here is that someone could piece together the entire book across dozens of websites of excerpts. How many people will go to the trouble of assembling all that content though? My point is that when I find a book I love I can usually think of certain excerpts that make it special. Why not let me share the pieces I find most interesting?
Next, you may have noticed the "Share" feature on the right side of the screen, just below the "Embed" button. The share option takes a link to the book and lets you email it, add it to your Facebook updates or tweet it. This is a nice step in the right direction but, again, I'd like to point to a specific excerpt, not just the book's catalog page. Also, Amazon, can you please add this "share" functionality to your Kindle apps, particularly the iPad one I use every day? Why should it be available on Kindle for the Web but not your individual reader apps?