Considering that Groupon is basically burning cash and that (until further evidence) their business model is unsustainable, I don't think that's a good example.
People should really compare Facebook to Google.
Google post-IPO was valued at a "bubbly" 27 billion in 2004. And take note that at that time Google already proved it had a viable business model; but people were still freaking out because Google only had one product, compared to what Microsoft or Yahoo had.
Are you going to tell me that Facebook is worth three times as much as Google did in 2004?
It's challenging to compare an Internet company in 2011 to a freeze-frame of one in 2004.
The better comparison is to Google today, which is worth $171B. Is Facebook worth 2/3 as much as Google? It certainly could be, since if it assaults Google head-on in an ad network, given certain other assumptions it could capture a huge market position.
Groupon would never get a $6bn offer today, and to pretend like that is what I was proposing is absurd. Their market position and future prospects has significantly slipped from what it was. We can only speculate if that would have occurred had Google acquired them or if they would have managed it better.
The exact same line of thinking that you are using would allow you to say "Here's a source that puts Myspace above Facebook (Alexa rankings from 2008), and most likely had higher ad revenue at that time. MySpace just sold for $35m so how can you say Facebook is worth even $100m?"
Valuations of tech companies is largely based on future projections and the future projections of Groupon has shifted in the past 6 months just as significantly as MySpace did in the last 3 years.
People should really compare Facebook to Google. Google post-IPO was valued at a "bubbly" 27 billion in 2004. And take note that at that time Google already proved it had a viable business model; but people were still freaking out because Google only had one product, compared to what Microsoft or Yahoo had.
Are you going to tell me that Facebook is worth three times as much as Google did in 2004?