Marvin Olasky explains:
Among the excellent books of the past 12 months one stands out:
Crossway's English Standard Version Study Bible. To the accuracy and
readability of the ESV, it adds 20,000 notes based on top evangelical
scholarship, 80,000 cross-references, 400 maps and charts, and much
more, all under the supervision of two splendid theologians, Wayne
Grudem and J.I. Packer.
[more]
Me: I bought a copy on sale last Christmas and like it a lot. It's a hefty "tome," and thus not handy for carrying around. But what I especially appreciate is that it is fully accessible via the internet. I appreciate the notes and the hyperlinks that make Bible study fast as well as enjoyable and profitable. And, in general, I prefer the greater literalness of the ESV to the NIV. Highly recommended!
Update: See my earlier post: "Online Bible Reading Plans (with Sound!")