I don't think that the amount of advertising on Facebook at the moment is that bad, although some of the adverts themselves are ridiculous.

Having had a scan through some blogs it seems that the German version, studiVZ | Bist Du schon drin? has also received similar criticism but the advertising on that site really is quite intrusive. Some times you'd think you'd been redirected to another site because of the amount of flashing banners and advertising images. One blog did mention the possibility of users being able to "switch off" the advertising if they wish. Perhaps this could be an option with Facebook? Afterall consumers love choice...