Ars Technica's Anders Bylund does some guesstimating about the total losses incurred by Newscorp in their purchase of MySpace, coming up with a figure of at least $1B, including operating losses since the acquisition.

So all things considered, MySpace has cost Murdoch's empire something like $1.3 billion. Even if my assumptions are way off, the final cost can't be less than $1 billion. That fiasco isn't putting Murdoch out of business: News Corp turned a $2.9 billion dollar profit in the last four quarters and generated $2.2 billion in free cash flow, for example. But it still stings as Murdoch's dreams of an end-to-end interactive media empire falls apart. And his shareholders have been trailing the broader market as well as rivals Viacom and Disney over those five painful years.