Between a camera backpack or roller bag, my first choice would be a Roller. It's an easy way to carry equipment without stressing out your back and shoulders. The problem is that these rollers are difficult to work with when navigating through very crowded events (like CES), so a backpack ends up being the better choice.
At just under $380 dollars, it's one of the more expensive bags on our list, but we needing something durable. When traveling for several days, dealing with something as simple as a broken zipper could be all the difference. From reviewing several other products, the Tamrac 5797 Evolution Speed Roller Backpack was the best one we felt was built to last, provided the convenience of a roller, while offering the best comfort as a backpack.
There is plenty of room for a few camera bodies, several lenses, audio equipment, misc accessories, and a full sized Macbook Pro Laptop. The Tamrac 5797 Evolution Speed Roller Backpack is still sized to carry on a plane so you don't have to check your gear when you fly.
Here's a great LowePro camera backpack design shared by Habez [Thanks Habez]. The DSLR Video fastpack was released more than 6 months ago, but it's pretty much set up for something I would use. I normally always carry a laptop (mobile blogging) and enough camera equipment to do a basic shoot including a small portable tripod. The LowePro FastPack 150, 250, and 350 are designed to hold a decent amount of Photo or Video gear for fast access. The largest 350 version is wide enough to support a 70-200mm Lens, and room to store a large 17" Laptop, along with Tripod holder and Rain Cover.
Other highlight features
Security Flap for additional protection to outer compartments, Built-in Memory Card Holders, 180-degree Side-entry Panel, Adjustable Dividers, Triple Compartment Design, Harness Pocket, Outer Accessory Pockets, Mesh Side Pocket, Tough Water Resistant Outer Fabric, Side-entry Access. Starting at about $100 dollars for the smallest on Amazon (Click Here).