More detailed financials from WSJ Deal Journal on the economics for Hellman and Friedman.
UPDATE: Turns out we were a little light in calculating Hellman's take on this deal. The firm, along with a few other investors, put in about $330 million of equity to purchase the company. Adding in $435 million from the previous sale of the business that used to be called Abacus, that brings the total to around $3.5 billion. There's even a word for this kind of return: A killing.
So we are talking (very roughly) about something in the range of a 8x return in a year and half (once the debt was paid off) and $500M in carry for the GP. Very impressive.
Of course the big loser is this is not Microsoft but the sellers of Double-Click in 2005, who left a few billion dollars on the table...