[timr]

Just because you join a company pre-IPO doesn't mean that you automatically get rich. If Google employees are really jumping ship for Facebook IPO riches, then I sincerely hope they've been given truckloads of stock units, because joining as employee 1200-whatever at Facebook means that there isn't much upside left in the share values.

In particular, if you start at Facebook today, the stock units you get are being sold on secondary public exchanges at frothy values. The stock is as close to fully and fairly valued as it's going to get short of an IPO.

[unshift]

you don't have to get rich for it to be worthwhile.

i joined a company a year before its IPO, got a modest number of shares, and it amounted to a nice little bonus every month. didn't make me rich but allowed me to build up a lot of savings while paying down my mortgage. it's totally worth trying to get into that situation if the option is available.

[bretpiatt]

This assumes you only get options and not restricted stock units. With the accounting changes in the way corporations have to value options many more now give out RSUs as well.