I waited so long for this news! The Gmail mobile blog has just pleased us with the fact that now we can synchronize our contacts and calendar using the PUSH technology. In a nutshell, this will allow you not to synchronize your (iPhone, WM, Blackberry, Symbian) manually - everything will happen in automatic mode. As soon as you update something on your phone or computer, the data will be changed on all devices.
I do not know how on other devices (I hope to write in the comments), but on iPhone it makes everything super-simple: just connect to your Google account by selecting Microsoft Exchange. And then everything goes like clockwork .