Alright, I think this is going to be a tight fit, but if you can leave out a cup or maybe take a few sposies for outings, I think you'd be good to go. then again, there's always the BePrepared... I have that, too
I had to pack it a few different ways before it fit. **Disclaimer: Please don't mind the wrapping paper and trash/toys on the floor in the background... it's Nolan's birthday today, and his presents are currently covering my floor LOL
Here we go:
All contents (the bag looks fat because my stuff is still in there). I included 5 cloth dipes (2 FB's, 2 BG 3.0s, 1 BG organic), a pack of wipes, 5 sippys, 5 baby outfits (which would be about the equilvalent of 3 toddler outfits), 4 sposie pull ups.
Two sippys on the outside insulated pockets, two on the back inside pockets (can't do inside end pockets because the outside pockets eat into that space and two cups back to back don't fit). Wipes and pull ups on inside end pockets. Outfits in the bottom.
Five dipes added along the top (and I despise "layers" in a diaper bag, so this would bother me but there is simply no other way to pack this many diapers and sippys together)
Zipped up, you can see I could not fit this one sippy. FWIW, I don't pack sippys in my bag, I use this-
http://www.onestepahead.com/catalog/product.jsp?productId=536676 to attach them to the stroller. I got mine at BRU for about $4 each.
Side view, you can see how packed it is, the changing pad pocket bulges a bit. I don't have the backpack straps attached, I'm using the messenger strap.
And for reference, you could still use this front pocket to add your wipes or something else to save space in the main compartment. I keep hand sanitizer, a crayon roll, table covers, baby hat, money, chapstick, feminine pads, breast pads, first aid kit, hair brush, wet wipes, boogie wipes, etc. in there. If this was all removed you could easily make use of this space.
I hope that helps you.