The Goal - Reduce Email Haze When Using Gmail
I need to automatically segment non-critical emails (e.g. notifications, newsletters, etc.), but the "multiple inboxes" Gmail labs feature confuses me.

The Solution
Use Gmail filters, creatively!  Create a filter in Gmail that will auto-archive and place the types of email I wish to filter into labels.  Now they will not clutter my inbox and distract me, but I will still be able to see the unread count to detect spikes in relation to each label, and so I can spot channel partners that I have been in discussions w/ signing up.  Once I read the emails within the label, I then remove the label [this is key].  In this way, I have created multiple inboxes.  The only downside is that labels do not show in mobile phone email clients.  So, if you mimic this system, only create filters and auto-archive to labels for non-critical emails, if you use or intend to use a mobile phone in conjunction w/ your computer.  In my case, we have a customer support team that address our order notifications, so these emails are non-critical.

The system is:

1. For the emails you wish to segment away from your inbox, create a filter;
2. Auto-archive to an appropriate label;
3. Remove the label upon reading the emails, this puts it in Gmail's regular archive and removes it from your label which you are using as an inbox.

It would be easy to let a system like this get cluttered, so I am going to keep my labels to a minimum.  At present, I have the following labels: Disqus (blog comments); Facebook; Order Notifications; Newsletters. 

Staying focused throughout the day is critical.  By removing non-critical emails from my primary inbox, I am reducing the amount of information I personally need to filter through during the day.  This improves my focus!  Since I am batching non-critical tasks, I am being more efficient.  Plus, in those times when there are not enough hours in the day, I can prioritize easily by not reading Newsletters and Facebook notifications until the weekend.