Activision (ATVI) soars 17.9% following news it's buying back $5.8B in shares from Vivendi at $13.60 each (10% discount to last night's close). The deal is expected to boost EPS this year by 23-33%. CEO Bobby Kotick notes the mostly debt-financed purchase allows the company to take advantage of attractive financing while still retaining $3B of cash on hand. (PR)