Microsoft (MSFT) - long candidate ?

- ticker = MSFT (NYSE)
- current share price = 20.33 $
- book value per share = 4 $ (approximately)
- earnings per share = 1.90$

Microsoft stock is currently priced at a PE of 10. This looks like one opportunity in 20 years time.
Imagine the scenario in 3/5 years: earnings per share at 2.50$, and a market valuing the stock at a PE of 15; that would bring the stock to a price of 37.50$.
This scenario is not absurd at all to me.

The risks ? well earnings could go down due to the current global economic slowdown, but Microsoft looks to me like a real Warren Buffet pick, with a monopoly, a difficult position to compete with, with very profitable business.
I guess the only reason Warren Buffet does not buy it is that he does not buy what he does not understand as he said several times.