Since examining my beliefs along with the bible I see prayer as providing comfort for those who hear it and maybe those who say it even more. I personally don't think God is recording our prayers.
If God was to care as much as any parent then he would know what we need before we mention it verbally or even think it.
I agree...God knows what our needs/wants are before we even speak them. But I do believe He's listening. So why do I pray? Not because God needs to know...he already does...but it's communication. Your wife may know that you love her...but you telling her the actual words is communication of that love. It's an exercise of confirmation. So yes, our words during a prayer are comforting to us and those around us. But to me it's more than that. It's an exercise for me to communicate with my Father. I share with Him because I love Him and want to have a closeness with Him that I can only accomplish through prayer.
Just my two cents...