[potatolicious]

I've been at Google fairly recently, that's not how it works.

Your offer states that you will get $X of shares, vesting over 4 years. The $X is converted to a number of shares shortly after joining, based on market price, and is locked in from that point forward.

Your friends are mistaken.

[QuercusMax]

This is correct. I believe the share-price they pick is something like the average daily share price for the next full month after you join. So if you join Jan 28, the $$ value of your stock grant will be evaluated around March 1 to determine your grant-price, and then you'll get your first vested shares monthly (around the 25th, I think?).

I believe they used to due quarterly vesting for folks who didn't get much equity, but now that you can have vesting of fractional shares, ~everybody should be on a monthly vesting schedule.