The Lamb's Book of Life---Written when?

Can you remember being in church services that closed something like this?

Every head bowed, every eye closed, no one looking around, instruments playing softly, now raise your hand and look up at me if you would like to have your name written in the Lamb's Book of Life tonight.  Is your name written in the Lamb's Book of Life?  Would like you like it to be?  Then as soon as we start singing, if you will walk down this aisle and take me by the hand, pray this prayer, do this and that, jump through this hoop and that hoop, etc.,  your name can be written down in the Lamb's Book of Life tonight in Heaven..........Now, how does it feel to know your name has just been written down in the Book?

Is this correct?  I believe Scripture teaches the Lamb's Book of Life was written before the foundation of the world, not at a moment in time when you make your "decision for Christ".  Agree?  Disagree?  I invite you to read on if interested...

I can remember end-of-church-service invitations very similar to this growing up in a Southern Baptist Church in Louisiana. The Pastors, Preachers, Evangelists, etc. speaking like this were great men of God who loved Jesus, and they were instrumental in bringing many people into the Kingdom of God (both wheat and tares, no doubt, but didn't Jesus say they must both grow together?  see Matthew 13)

Now, is there anything wrong with that type of "invitation" or "invitations" in general?  Glad you asked, but I'm not going there on this blog.  There's much debate over invitations, and people feel strongly on both sides of the debate, but I know God is not hindered and His arm is not shortened that He cannot save, regardless of our "methodology". Countless multitudes of souls have been saved with and without invitations because it is God who does the saving by the power of the Holy Spirit through the preaching of the Gospel, not us or our invitational methods.

 The reason I was thinking about the Lamb's Book of Life today has to do with a facebook post by R.C. Sproul earlier today, as follows:

 Ligonier Ministries FACEBOOK post:
When God writes our names in the 'Lamb's Book of Life' He doesn't do it with an eraser handy. He does it for eternity. - R.C. Sproul

The comment thread was getting longer and longer, and I noticed no one seemed to mention what Scripture says about this, but only made comments about Revelation 3:5 and whether or not we can be blotted out of the Book.  So I put my two cents worth in (a metaphor for "my opinion", for those International readers  that may not be familiar with American English "figures of speech").  The following is my response on Ligonier's thread:

Actually, our names aren't written in the Lamb's Book of Life when we're saved, they're already there from before the foundation of the world... Rev.13:3 (NASB) speaks of "those whose name has not been written from the foundation of the world in the book of life of the Lamb", and Rev.17:8 (ESV if you prefer) speaks of those "whose names have not been written in the book of life from the foundation of the world"...so the names of the elect are already there, which coincides with Ephesians Chapter 1, Romans Chapter 8, etc., and the promise is that they will never be blotted out in Rev. 3:5, because cities in that day would blot out or purge the names of undesirables from their city register...the promise is that this will not happen to us who are secure in Christ...

Arthur W. Pink's last words before he died in 1952 were:  
"THE SCRIPTURES EXPLAIN THEMSELVES!"

So in summary, according to Scripture (and Scripture is our only Authority), the Elect's names are already written in the Lamb's Book of Life before the foundation of the world and will never be blotted out.  

But you might say "then what's the use for me, if I'm not elect, I don't have a chance. "
Well, I'm glad you asked!

John 1:12-13 (ESV) says

But to all who did receive Him, who believed in His name, He gave the right to become children of God, who were born, not of blood nor of the will of the flesh nor of the will of man, but of God.

and Revelation 22:17 says  The Spirit and the Bride say, “Come.” And let the one who hears say, “Come.” And let the one who is thirsty come; let the one who desires take the water of life without price.

So if you're not sure of your salvation, or if you know you're not saved, and if you are being convicted and drawn by His Spirit, if you will humble yourself, cry out to Him and sincerely surrender to Jesus Christ as Lord and Savior in repentance and faith, you will find that your name has already been written in the Lamb's Book of Life.  
But if you continue to reject the Lamb of God who takes away the sins of the world, you will one day (perhaps judgement day) see that your sins remain on yourself, and that your name is not in the Book.  How tragic that would be...