The holster design has been a staple of camera bags for a long time. Lowepro's Cirrus line is a new take on the holster design. If you're not familiar with the holster-type camera bag, it's based on a triangular shape, tapering toward the bottom, and holds an SLR or SLR-type camera, typically with a small zoom lens. There's not too much you can do to update this idea, but you have to hand it to Lowepro, since they do a great job of modifying simple things and giving them a classy contemporary look.
Like all holster bags, the Cirrus TLZ 25 is a top-loader. Inside the top flap you'll find a small pocket for memory cards or other small items. The top flap opens away from your body when wearing the bag, which is more ergonomically sound than the opposite way. Unfortunately, there's no place to store a hot-shoe flash unit in this bag, but that is common for holster bags. On the plus side, the Cirrus TLZ 25 has a belt loop if you're the type to wear a camera bag as though it's a fanny pack.