The gemara makes a famous statement that Hashem gave MORE bina (understanding) to a woman than a man. This implies that on some level a woman has a greater mental capacity than a man. However, in the context of the gemara, as pointed out by the Tosafos HaRosh, the gemara is simply saying that a woman matures and her mind develops prior to a man. It is for this reason that she is considered to be an adult at the age of 12 whereas a man must wait another year. According to this approach the gemara isn't making a comment about the amount of understanding being greater in a woman, just the time that they develop their level of understanding.
The Torah Temima in Parshas Eikev (11:9) discusses why the Talmud considers women to be exempt from the mitzvah of Talmud Torah. He raises a contradiction between our gemara which considers women to be superior in the realm of Bina, and the Talmud's comment in Sota that women are da'atan kalos - light headed. The Torah Temima explains that Da'as refers to the מושכל ראשון, the initial assessment of a situation. Bina refers to the ability to analyze, disect and understand deeply. The Torah Temima explains that women have a greater Bina but a weaker da'as, therefore their initial recognition of the material isn't as sharp. When they apply Bina to a less sharp picture, their analysis of the material ends up being distorted. However. men have a weaker bina and less ability to dissect the material, but a sharper מושכל ראשון, which enables them to have a more accurate picture although not as in depth of an understanding.
The entire approach of the Torah Temima is based on the assumption that שנתן הקב"ה בינה יתירה באשה יותר מבאיש, means that women have greater Bina. But, according to the Rosh the contradiction between Bina and Da'as isn't a question since the Bina is not greater, just comes to women at an earlier age.