Somewhat yes but there are going to be plenty of people who are going to suggest a different card. Likely the 660ti or 7870 usually. Going with a 580 will bring a few surprises to you considering that you got a 260. If your card is the 55nm model then the power consumption of the 580 is easily double of what you own atm and if it is the 65nm model just figure in 100w more than.
Performance wise it will beat two gtx280/285 in sli with ease and compete with more current cards like the 7850 ect.