My guesstimate for the Wallstreet “whisper” number is $2050M in gross revenues for Q4-2005, that would represent a 30% increase over Q3-2005 (the consensus official estimates are obviously less than this).
I reason that Google will miss that 30% sequential growth since their Q4 search PVs only grew by around 8% from Q3 (src: Comscore). That would mean that their RPS (Revenue Per Search) has to grow by 20%+ during Q4 to bridge the gap between 8% and 30%. I do not think is feasible without significant changes, e.g. more ads above the results, larger descriptions for the ads, or significant increase in CPCs.
In 2004, Google search PVs grew by 14% from Q3 to Q4, and their revenues grew by 28%. So RPS just needed to bridge the gap between 14% and 28%, which is doable; given that they were making lots of monetization improvements at the time. However, its very hard for the RPS this year to close the gap between 8% natural search volume growth and the 30% anticipated by the bulls.
Anyway, on Tues Jan 31st all shall be revealed …