I couldn't care less about their mobile strategy. In order to make $20 a fair price, they need to at least quadruple their expected earnings.
What concerns me is the amount of time and effort people spend trying to buy these garbage stocks because they are in the news, trendy, their kids use it, etc.
Even in today's grossly over valued market, you'd be better off building positions in 100's of energy stocks, dozens of industrials (see CAT's earnings recenty?), or even preferred shares/fixed income closed end funds than wasting time on Facebook. Facebook is not just a gamble - it's a stupid gamble and the hype has cost a lot of small time "investors" (I have another name for it but I'll remain polite) a lot of money. Everyone was having a near orgy purchasing FB but very few came out in public afterwards about their (probably massive) losses.
The purpose of owning stocks is to make money. If you can't tell how, when, and why a company's stock is going to rise (99.99% cannot, including me in at least 50% of cases and I traded millions of shares on the NYSE, AMEX, etc.) you'd better be focusing a lot on yield and determining if that yield is sustainable and under what conditions it'll deteriorate.
I see your point, but as you said the purpose of owning stocks is to make money, and in order to make money effectively you need learn how to follow the big money. If those money managers/fund managers want to pump up FB stock (or any other stock), the stock will rise 30, 50, 100% regardless of having a PE of 50, 100 or 200. The stock market is rigged - it's an unfortunate truth. To be successful in the stock market fundamental alone is not enough, chart reading is very important - a picture is worth a thousand words.