I think the PI argument is not the strongest argument against Bible inerrancy. Surely, it is not what you'd expect to find in a divine document, but as examples of Bible errors, it is a not the best one.
Indeed, even the Alt.Atheism FAQ, that cannot be considered the most bible-friendly document in the world, dismisses this argument. See http://www.infidels.org/news/atheism/arguments.html#pi
Here's a small list of Bible errors that are much more serious:
There are countless (no pun intended) examples showing that Bible authors could not count, and they could certainly not calculate. Check Numbers 3:33-39, Ezra 1:9-11, Joshua 15:21-32 or Joshua 15:33-36 if you don't believe me. Considering the number system and educational level, that should not surprise us. But I guess God can count.
II Samuel 23:8 These be the names of the mighty men whom David had: The Tachmonite that sat in the seat, chief among the captains; the same was Adino the Eznite: he lift up his spear against eight hundred, whom he slew at one time.
I Chronicles 11:11 And this is the number of the mighty men whom David had; Jashobeam, an Hachmonite, the chief of the captains: he lifted up his spear against three hundred slain by him at one time.
Errors of Science
Insects have four feet (uh?):
Leviticus 11:20-23 "All fowls that creep, going upon all four, shall be an abomination unto you...Even these of them ye may eat; the locust after his kind, and the bald locust after his kind, and the beetle after his kind, and the grasshopper after his kind. But all other flying creeping things, which have four feet, shall be an abomination unto you."
The two most obvious are the birth accounts we find in Luke and Matthew, and the trial, death and resurrection accounts we find in all the gospels.
The birth accounts are so fantastically contradictory they agree on only a single basic fact: He was born in Bethlehem (he had to be, right?). Problem is, nothing else connects, and it's clearly impossible to harmonize the stories. If you don't believe me, try. One simple example:
Luk 2:22, 39 "And when the time came for their
purification according to the law of Moses, they brought him up to Jerusalem to present him to the Lord . . . And when they had performed everything according to the law of the Lord, they returned into Galilee, to their own city, Nazareth."
Matt 2:14, 15, 22, 23 "And he rose and took the child and his mother by night, and departed to Egypt, and remained there until the death of Herod. . . . But when he heard that Archelaus reigned over Judea in place of his father Herod, he was afraid to go there, and being warned in a dream he withdrew to the district of Galilee. And he went and dwelt in a city called Nazareth, that what was spoken by the prophets might be fulfilled, "He shall be called a Nazarene."" (which of course no recorded prophet ever said!)
The death accounts contain somewhat more common details, but also differ in many respects. Nobody can make any harmonization of all the claims made in all four gospels. One minor example:
Mark 16:7,8 "But go, tell his disciples and Peter that he is going before you to Galilee; there you will see him, as he told you." And they went out and fled from the tomb; for trembling and astonishment had come upon them; and they said nothing to any one, for they were afraid."
Luk 24:9 "and returning from the tomb they told all this to the eleven and to all the rest." (also Matt 28:10, 16)
It's a logical impossibility that these women both "told nothing to no one" and "told all this to the eleven and to all the rest."
So much for inerrancy.
"Common sense is the collection of prejudices acquired by age eighteen"
-- Albert Einstein