The Wall Street Journal has a good overview and recap of the negotiation process.
Facebook is reported to have circa $150 million in revenue currently (and are launching their own advertising platform shortly). As a point of reference, Facebook’s revenue is worth 7.1x more on a price/sales basis than Google.
Looking back at the last round of venture funding, Accel participated in the $25 million round at a whopping $500 million pre-money. This was before the site was adding 200,000 users per day. Not a bad paper return given the price they bought in at… Now, how long until Facebook a) implodes or b) goes public?