+1. I have a closet full of bags but I'm always looking for others to fit specific situations. The quest for the perfect all-round bag never ends. My wife claims I have more camera bags than she has purses.
And like Eurotrash said, everyone has their favorites. If you ask 10 people to recommend a bag you'll likely get 15 different answers. Still, it's useful to see what folks like and don't like. But always remember that they may not have the same requirements as you. For example, do you travel with your gear? That's different from carrying a bag around town.
Of all the bags I own these are my favorites for different situations:
1) Light carry (one body, one lens) - Lowepro Toploader Zoom. Just right for light needs but screams "Camera!!".
2) Around town (one body, one or two lenses, hoods, cleaning supplies) - Domke F-6. Great everyday carry bag. Lightweight but made of heavy canvas so it molds itself to your hip. Doesn't stand out as a camera bag. These bags will last a lifetime.
3) Travel (one or more bodies, multiple lenses, extra packing room) - Tenba Shootout Sling. Similar to the Lowepro Slingshot but I much prefer the Tenba. These bags are tough and well padded for extra protection. Easily fits under a commercial airplane seat.
4) Hiking - Tenba Shootout Sling (again). Comfortable to carry, quickly slips around for fast access.