This is a gross misuse of Warren Buffet's famous quote to say the least. I would highly recommend reading about Warren Buffet's investment strategy -- he never talks about buying into the latest high tech IPO. Investing in hot IPOs (or even hyped IPOs) isn't at all how he made his money. He bought into boring industries that everyone was basically ignoring and then he helped them increase their margins by bringing in very good management that was focused on the long-term bottom line. The management at Groupon is very scary as they are clearly cashing out and are not looking at the long term at all.

Also, if there is general negative sentiment (not just isolated as it is now) about Groupon, there won't be an IPO. It could easily be withdrawn and if it is withdrawn, it likely won't come back if what everyone is saying here on HN is true.