I've always felt uncomfortable with this. I don't mind saying that the Bible is true; I'm all for saying it's authoritative; but to say it is inerrant is to drift into a realm of danger. The fall-back position of the evangelical (especially, the Calvinist) Protestant is to say, "Because the Bible says so." But if one is not careful, this becomes, "God so loved the world that he gave us an infallible book," rather than ". . . his only-begotten Son."
A couple years ago, I bought a book by Gilbert Bilezikian called Christianity 101. This book is used in teaching ministries at Willow Creek Community Church, where Bill Hybels is the pastor. This is one of those mega-churches we're all supposed to try to be like. Bilezikian carefully establishes the basis of Biblical (especially, New Testament) authority -- the experience of Christ transmitted through the Apostles. Having shown how we got the book and what it's good for, he pitches the Apostles like a used tea-bag and presents us with The Book. Propositional Truth here we come: proof-texting par excellence.
Now, I'm not trying to exalt some human agency in the place of the Apostles. Neither Church tradition being reinterpreted to meet new challenges (the mainline Protestant temptation), nor Papal Infallibility, nor the Mormon Prophet-Presidency is acceptable to me. But neither is treating the Bible as a homogenized mass of text to be winnowed for The Rules.
The Bible contains many different kinds of literature. Each kind is true in different ways. Poetry may transmit truth, but it is not "true" in the way a newspaper (or history book) strives to be "true." Visions may be "true" -- but not everything in them is to be taken literally. Folk wisdom (e.g., Proverbs) and philosophy (Ecclesiastes) have different paths to truth. To treat any sentence in the Bible as interpretable by another other sentence in the Bible w/o a lot of contextualization is a recipe for true-sounding falsehood.
I guess what I'm saying is that I believe the Bible; I don't necessarily "believe in" the Bible (Note: I believe in Jesus Christ). As Charles Williams said of a different age, wrestling with a similar problem, At least Society believed in belief; it believed in the Creed, even if it no longer believed the Creed. I see lots of people who believe in the Bible; I see others who merely believe the Bible. There is a fair amount of overlap between the two groups, but they are not the same. (And then, there's all those people who think the Bible is simply unbelievable, or a lumber room from which to take bits and pieces to construct their own belief system. This is not about them.)
I believe the Bible is, at bottom, an old book. It should be taken as such. The problem with most Biblical Studies, however (both liberal and conservative) is that nobody treats it that way. The liberals say that this book makes such huge claims (or such huge claims are made for it) that we must not evaluate it like some ordinary old book. Extraordinary tests must be applied to it. (The fact that these tests guarantee that the Bible will fail them is not allowed to be talked about.) Meanwhile, the conservatives say that this book is so obviously divine (at least, in origin) that it would be impious to evaluate it like some ordinary old book. (The result is that all their criticism tends to beg the question -- and this isn't allowed to be talked about, either.)
But if the Bible were to be allowed to stand up as just an old book among other old books (Gilgamesh, Beowulf, Iliad, what have you), then its obvious value would knock your eyes out -- in just the same way Jesus did. "Never spake man like this man!" they said. But then, all he looked like was just another guy; if he had come claiming divine inspiration up front, factions would have formed immediately to debunk him or boost him -- and neither would have allowed people to just hear him.
So, yes. I believe the Bible. I submit to its authority, and test all things by what it says. But I'd rather have a whole congregation of people who actually read the Bible, than who said that they believed in it.