Mmm, I'm a nappy bag addict hun! I have four. But one that I use most of the time (Nine West) followed closely by another (from a nice baby shop, can't remember the brand). My Silver Cross one lives in the boot of the car, carrying spares of just about everything, should I ever get stuck, or run out. And the last one is the one I used for my pram with DS1, I will use it again, just not ATM cos I'm not using the pram much.

I love lots of pockets, inside and out. That way I can organise the bag to my hearts content, and know where everything is quickly. I DEFINITELY don't want to take two bags with me anywhere, a nappy bag HAS to fit everything in. Once DS1 was about 15 months I started using really big handbags instead of a nappy bag. I had a CR one that I loved, it was really great!
Good luck choosing, and have fun! Can't wait to see it