Why would anyone follow a God who can't make up his mind?

When God set out to destroy Israel, after they turned to idolatry and worshipped a golden calf, His mind was apparently changed by Moses.  You can read about this in Genesis chapter 32.

Some say that a God who changes his mind is ridiculous so that either the bible is wrong or the God of the bible is not worth following.  Some even think that this means you can make God do what you want (like giving you material things if you just have enough faith).

Here's a scripture to put this into perspective:

"Remember this and stand firm, recall it to mind, you transgressors,  (9)  remember the former things of old; for I am God, and there is no other; I am God, and there is none like me,  (10)  declaring the end from the beginning and from ancient times things not yet done, saying, 'My counsel shall stand, and I will accomplish all my purpose,'  (11)  calling a bird of prey from the east, the man of my counsel from a far country. I have spoken, and I will bring it to pass; I have purposed, and I will do it.

- Isaiah 46:8-11  

If God knows the end from the beginning, and he will accomplish his purpose, do you really think he didn't know what he would choose to do in the end?  Since he clearly knew, do you think he really changed his mind?  Isn't it more likely that this exchange is either recorded from Moses' perspective, or that we need to read a bit closer to see what's being said?

If you read Genesis 32 carefully, you can see that there was no change of mind in any case.  God merely relented from pouring out his wrath on Israel.  If that's too weak for you, at least know that God had already made up his mind because his purpose will be accomplished no matter what we want.