Double Take!

I have a story to tell and then a question to ask.
Last night Derek and I went to the video store to rent a movie for our date night. I get out of his car and I'm walking next to him into the store when two guys walk in front of us. One of them very obviously looked me up and down, then did a double take... then ANOTHER ONE! Seriously? I was walking into the store holding a guys hand and you still look me up and down? I'm not saying it wasn't flattering... but if a girl were looking Derek up and down while I was standing next to him, I would a little upset. He took it as a complement. I'm just curious here...
Why do women have a different idea of what is acceptable and what isn't as far as flirting? And how exactly do men view flirting? I think I could really go on and on about this subject, but I would really prefer to find out what everyone else thinks before I give my input.
Thanks for your consideration! : )

Introduction

Alright, here's the scoop

I've been encouraged by a dear dear friend of mine (who is male by the way. This is important.) To write a book that I've been jokingly discussing for sometime now. The idea is to address all questions men have on the inner workings of the female mind. I'm not exactly sure how this is going to look yet, but I do know I need your help. Please give me some insight on what you would be looking for. Men, what confuses you about women? Women, what do wish men would understand about you? Please be as specific and up front as you possibly can be. Comment on eachothers posts, argue, praise, whatever moves you!
I will be posting my own questions as well, this is research. The more acurate information I receive the more informing I can be while writing.
Thanks for you support and I can't wait to get to know you all!
Sasha