Re: What are the religious inclinations of the top wta players?
If I was cynical I would say that Sharapova's Orthodox Cross is part of her brand. She's put a lot of effort into ensuring that her status as a sex symbol has remained on the classy end of the spectrum. In Russia, respecting religion is often the mark of a 'good' girl. The cross emphasises that - this girl might be amazingly sexy, but she's still the girl you could bring home to your family.
I know lots of women who wear (Orthodox) cross even though they're not really religious and definitely without the intention to send a message of some sort. Quite often it really is little more than a simple fashion item.