Serena Williams: 14 Grand Slam singles titles, 15 Grand Slam doubles titles, 2 Olympic golds in doubles, and with a 6-1 6-0 piledriving of Maria Sharpova today in London, Olympics singles gold. She's the first woman to earn at least one each of all 10 in a career "Golden Slam".
Also, this happened when she won.
Winner. I'm gonna say best of all time at this point. 32 major wins, 31 years old. She still have half a dozen years left, I would think. Yes, Steffi and Martina have more singles titles, Serena has more overall counting her doubles wins with her sister Venus. She can play both styles and dominates them both on any surface, period.
I'd say that qualifies her, yes?