It sounds like a clever idea, but then again someone once thought the <BLINK> attribute was a clever idea.
I find the popups to be very annoying. If you are trying to read something and you move the mouse over one these snap-enabled links, your experience has been disrupted. I'm not the only one who dislikes SPA.
The idea is to show a preview of the site behind the link so that you can tell if you want to click that link. Come on people, it's 2007 and our browsers have multiple tabs. No mysterious force is preventing me from opening that link in a background tab.
The good news, it's pretty easy to fix. You can disable the popup by going here and scroll down to the "Snap Preview Anywhere Activation" block and follow the instructions. That method requires that your browser allow cookies.
If you are using FireFox, you can really take the snap out by installing AdBlock Pro and adding snap.com to the list of blocked sites. That works very nice.