Bartender has become an essential app for my Macbook Air. As the number of menu bar icons has increased, it has only become more important.
I basically keep the six most important icons up there (Fantastical, Sticky Notifications, WiFi, Volume, Battery, in addition to the time, Spotlight and Notification Center).
Hidden away are the distracting ones (Wedge, Tweetbot, Trillian, Hiss) and the ones that I use occasionally like Moom, Hazel, Crashplan, Bluetooth, VPN, Clocks, Syncopy, Dropbox, Droplr).
If you're not using the new 1.0 version of Bartender, you're missing out.