Is Facebook ready for its IPO? or Too Late?

As Facebook prepares its final run into its IPO (the company is looking at a 90-100 Bn dollar valuation at a $28-$35 value per share), the prospectus let us into some of their very interesting and well-kept numbers.  Inevitably their impact is two-fold: first, we can understand more on the social-media powerhouse, but secondly, we can also see where it's having growth pains.  The most relevant information therein contained is here:

The fact alone that Facebook is near 1 Bn users is astounding.  However, things must be seen in contrast: I have repeatedly heard "Facebook is the new Hotmail", in comparison with Microsoft's popular webmail service.  The comment comes from the fact that Hotmail was the standard way for content (video links, jokes, pictures, etc.) to be shared in the late 90s and early 00s), and most of this is now done on Facebook.  So, I conducted my very quick figure comparison:

If we trust these quick numbers, then the answer is NO; Facebook appears to be larger in terms of penetration of internet users in 2012 than Hotmail was in 2000 (39% vs 23%).  What could be argued is that what should be taken into account are active daily users, however, that information is not readily available for Hotmail in 2000.  If we compared Facebook's current daily active users - 58% of total or some 526 million, and assuming all of Hotmail users in 2000 connected daily, then it would be a technical tie at 23%.  The longer answer is then MAYBE, JUST MAYBE, Facebok is the new Hotmail.  If it is, then it must also be aware that it might be as safe as the T-Rex in the late Cretaceous period ... IPO or not.