Why do you think womens tennis manages to be almost as popular as mens tennis?
Actually, I have to disagree with your premise. Women's tennis isn't anywhere near as popular as men's tennis, especially live. However women's tennis does have a couple of players who are ridiculously popular with TV audiences, Venus and Serena Williams. Considering how much TV money drives tennis, that does make up for a lot.
As to why women's tennis is as popular as it is? (Which is VERY popular, for a women's sport.) First of all the power is way up. Second, the speed is way up. People who are fans of athletes
watch now, which really wasn't the case in the 70's. And of course, since the players have to execute at that ridiculous pace, people frequently see some amazing points.
And some of it is Serena's Hollywood and Hip-Hop connections. Venus' too, but much more so Serena. A lot of people worship at the altar of celebrity. Serena does TV shows, has her own fashion company, and oh yeah, she's the best in the world. There's never really been an athlete like her.
The tour's popularity lies in the popularity of it's stars. There already Chinese who stay up to the wee hours to watch Peng play. Indians who get up early to Mirza live. And of course, there are a lot of Black folks who tune in to see Venus and/or Serena play. Some of them become fans of other players. My sister's a Capriati fan, and my Mom's a Davenport fan. but it was Venus that drew them to watching the sport.
I wouldn't mind knowing how much tennis viewership is up in Russia.