It used to be that you couldnt SOMETHING-w to close a pinned tab. If you did that, it would just gray out and when you clicked on it, it reopened in at the same location.

Now, it has to stay open, you can close w/o taking extra actions and it is always using memory for the full page.

I tell you all of this so hopefully you can imagine how much better it used to be and I can add you to the campaign to get the old behavior back.

For a while there the persistent-but-closed state of pinned tabs was coming in and out randomly for me (based on updates on whichever repository I was on).

I agree, the old behavior of having a dual-state pinned tab was VERY nice. I pretty much always have three pinned tabs now (GMail, GMail, GReader), but it used to be a few more. Now if I close GReader, which I do if I'm focusing down on working and know I won't be hitting it, it disappears - instead of that little placeholder.

I've been hoping re-enabling that behavior it was an option I just missed somewhere. I guess not.

Love the pin feature! Also note, anything you install via the web store can be configured to always open in a pinned tab by clicking on the little wrench when you hover over the app icon. For me it's Mail, Calendar and Grooveshark. Why would I ever close them?

Me neither. But I have multiple gmail apps open. How do I tell the difference? grah.

Have them all forward to one gmail account and manage them from there.

There's a "multiple inboxes" labs feature that would probably come in handy for this.

one's personal and one's my startup. probably not a good idea.

Positioning.

Tooltips on the tab.

Tooltips take about 2 seconds to show on mouse-over. If you had to do it all the time to figure out which account you're looking/peeking at, you'd go nuts.