Can I speed up the auto-dismissal of Notification Center banners?

I like Notification Center, but banners linger a bit too long before auto-dismissing.

I'm aware of the popular two-finger swipe trick to immediately dismiss a banner, but I'm looking for an automated approach. Growl, for example, let you customize how long notifications stayed on the screen, but I don't see a similar option in the Notifications preference pane.

Is it possible to adjust this, like perhaps through a hidden preference?

Although I never usually have any luck finding them, I used MacWorld's guide, "How to find hidden preference settings", and I was able to find the hidden preference:

defaults write com.apple.notificationcenterui bannerTime <SECONDS>

Type the above into Terminal, replacing <seconds> with the number of seconds you want the banner to last for, and press return. Then, log out and log back in to reload Notification Center.