Some considerations
A few points, perhaps not exactly what the OP specified, but worth thinking about for others: comfort, safety, utility.
First, any sling-type one strap or shoulder strap bag can get very uncomfortable in the long run, especially on slightly longer hikes or daytrips. Even just wandering around a city taking photos can tire out your shoulder/neck when you have only one strap. That's why a backpack type bag with two shoulder straps is actually superior.
Second, consider safety. There are two issues here. One, you don't want a bag that screams "there's a camera here, please rob me!" For that reason I avoid the obvious looking "camera bag" and avoid the usual black/grey colors. A single strap is again a handicap here - one cut with a knife and the robber is running away before you can catch him. The other issue is theft when you don't see. Let's say you are in the subway that's packed. Or even going through a crowd - you won't believe how skilled some pickpocket type thieves are. Most top or side "easy access" bags are vulnerable here.
Third, you want something that's relatively easy to access, has enough room, but is not too big, and has enough padding and rain protection.
With this in mind, I have my eye on the Lowepro Flipside (comes in different sizes). It's a backpack (comfort), it doesn't scream "camera bag", it has a unique access feature where you can only open it from the side that's against your back (you rotate the bag and it hangs at waist level in front of you like a table, then you unzip the back for access to your stuff). It has a special place for a tripod. It seems well made and offers enough padding. Here's a video of a demo (I'm not affiliated with Lowepro in any way):
http://www.youtube.com/watch?v=qwAOb3GjVcQ
Again, I haven't actually tried it out as yet, but plan on buying it later this month, at which point I can give a fuller report - I just thought I'd throw this out as food for thought

Incidentally, here's a site for camera bags, with user reviews, including a user review of the Flipside:
http://www.cambags.com/camera_mainpage.htm
Hopefully, someone finds this useful!