On the design: I love the clean aesthetic and color scheme. I would try to to make the page vertically a bit more compact, so the entire "Login using Google" is above the fold. I have a relatively large monitor, and yet only the top of "Login using Google" shows on my screen.

Then I'd test some descriptive instruction above "Login using Google" to explain why they should - the value to them. "Take a test drive and see how your social life improves - all you need is a Google account to get closer to your friends" - something like that, just make it shorter. Test different variations that answer the question, "why should I go to the next step?" It might seem obvious to you, but you're intimately familiar with your site. Me, why should I log in? The site looks nice, but what's the value here? What's the learning curve? Will this be a pain in the ass to get running? Mention how easy and fast they can do something cool, and then deliver on that promise once people log in.

Cheers mate, and best wishes.