A new best in the world?

Returning to the Polgar-Hou comparison a few months later, the latter hasn't been playing all that well lately (see http://www.chessgames.com/perl/chess.pl?tid=77784&crosstable=1 and the ongoing tournament in Kazan where she lost to 2333 rated Yildiz as well as Cmilyte). Her live rating is a bit below 2600, around the same rating she had more than three years ago, and she has fallen a few points behind the four years older Anna Muzychuk. Of course Hou is only 18 years old but considering that she has been rather stable around 2600 for several years the question is how easy it will be for her to ever get close to the top ten position Polgar reached. When Polgar was 18 her world ranking was already the same as title match participant Gelfand's in 2012. All players develop differently and it's hard to predict what will happen, but it's far from certain that Hou will be ahead of Muzychuk in a year or two.