So, as eager as I am too to obtain a monitor with G-Sync integrated into the monitor, I will have to wait until a 27" version comes out... hoping for 2nd Q of 2014 for a 27".
I'm fairly excited ViewSonic is one of the companies they have already working on implementing G-Sync. Imagine a VP2770 with low persistence g-sync. Even ViewSonic's gaming monitors have had pretty good image quality. My ViewSonic 120hz V3D245 absolutely destroys my Asus VG248QE in static image quality.
It worries me that ViewSonic discontinued the V3D245 and haven't had any high frame-rate displays for a few years now, but they did come out with the first 2 ms response time and 1 ms response time display so I'm still hopeful they'll create a great gaming display.
I concur with the statement that Q1 was the earliest we'd see G-Sync enabled monitors come to market. I'm hoping by the time an upper-midrange Maxwell comes out, there will be a ton to choose from.