I had heard about SafariU earlier this week while listening to an IT Conversations Podcast and remember thinking, "what's the big deal?" I figured you could probably just build permanent links to various chapters in the Safari Tech Books online database, so why pay to do the same thing through another interface?
As always, when I finally stopped to read about it and watch their tutorial I see that there's more going on here besides an easy interface. Turns out you're actually getting hard copy books as a result, which many will prefer (though not necessarily the distance student). You can also get online access to at least some of the content that was used in the text. In addition, it appears that SafariU can be used by faculty who don't necessarily have access to Safari Tech Books online, though if you find out any of your faculty are considering this route you might want to sit down and cost out access to the database vs the cost per student to create these textbooks.