The $450M to EMC is to a parent company. It is nothing in a total buyout.
Even if there will be no buyout, the payment of the debt is likely payed over a period of time longer than 4 years. It will be pretty much smoothed out by much faster cash increase from earnings.
I wouldn't be surprised by income growing 40% over the next four years.
Cash may be $2.9 billion, but they owe $450 million to EMC, so net cash is $2.45 billion.
As far as earnings, I think quadrupling them in four years, based on the scale the company now has, is highly unlikely.
Cash, cash equivalents and short-term investments as of September 30, 2010 were $2.9 billion, an increase of 32% compared to a year ago. Total deferred revenues were $1.5 billion, an increase of 52% from the same period a year ago.
Earnings/income should be able to quadruple in 4 years. The cash and equivalents should increased by about $1B. Quite possible: forward p/e in 4 years is at 10. Other significant software companies in 4 years? About the same. In 4 years, VMware will be still growing much faster than the others.