Posted by Bruce DiBello, Software Engineer
Today, whenever you open an email in your Gmail inbox and then archive or delete it, you’re taken back to your inbox. Many of you have asked for the ability to instead go to the next conversation. Keyboard ninjas will already be familiar with the “]” and “[“ keyboard shortcuts for archiving and going to the next/previous conversation. For everyone else (and for people who frequently mute or delete conversations rather than archive them) we’re offering a new feature in Gmail Labs called “Auto-advance,” which automatically opens the next conversation after you archive/delete/mute the one you’re on.
To get started with “Auto-advance” go to the Labs tab in Settings, enable it, and click the “Save changes” button. By default, “Auto-advance” will advance to the previous (older) conversation in your inbox -- perfect for people who read their newest mail first. If you usually read your oldest email first and would rather advance to the next (newer) conversation, you can change the direction from theGeneral Settings tab.

Hopefully this will save you some time the next time you have to deal with a crowded inbox. Try it out and let us know what you think.
The way Gmail organizes mail into conversations is like cilantro. You either love it -- and, like me, enjoy the nice citrusy, herbal finish it gives to everything from salsa to curry -- or you hate it. And those of you who hate it hate it enough to launch sites like nocilantro.com and ihatecilantro.com(“an anti cilantro community”), where you can hate it together.
But my fondness for cilantro pales in comparison to my love for Gmail’s conversation view, or message threading. I haven’t had to wade through multiple messages to follow a conversation in years. A centithread hasn’t filled up the entire first page of my inbox in almost as long as I can remember. Having all the replies to an email (and replies to those replies) grouped with the original message simply makes communicating so much easier.
It turns out not everyone feels the same way. And just as an outspoken minority has banded together in unison to declare their distaste of one of nature’s most delicious herbs, some of you have been very vocal about your dislike of conversation threading. So just like you can order your baja fish tacos without cilantro, you can now get Gmail served up sans conversation view. Go to the main Settings page, look for the “Conversation View” section, select the option to turn it off, and save changes. If you change your mind, you can always go back.
This feature will be rolling out over the next few days so if you don’t see it immediately, check back in a bit. And once you try it out, let us know what you think.
source cited: http://gmailblog.blogspot.com/2010/09/turn-off-gmails-conversation-view.html