luke-jr has added the Balance tooltip to Spesmilo shortly after I suggested this idea in #bitcoin-dev
From
https://github.com/bitcoin/bitcoin/pull/190:
Too features which I thought would be very useful is an easy way to view your balance without opening up the whole application, so I added the balance to the tooltip.
I also felt that adding a send coins option was nice, as there is even less reason to open up the whole bitcoin client just to send some coins.
Please note that I may not have done the translations (that is, used _()) perfectly regarding the tooltips, so please check that first.
