How can good (?) site be verified

I was wondering how I can verify if a supposedly good site is or is not a good site? In this case Coupons.com. Is there a way to make sure it is not shoving malware of whatever my way? My wife insists on using it as it has lots of good/valid coupons on it.

Here’s the Web of Trust report:

You can also check out McAfee SiteAdvisor, but I find it to be less relevant in general:
http://www.siteadvisor.com/sites/coupons.com

In general installing Web of Trust as an addon is a good way to recognize most bad sites. This site seems bad.

Indeed.

What about the Comodo Verification Engine? However, I see it is listed only for OSes up through Vista and I am running Windows 7 64-bit. I’ll give that a try and see what happens. Then again, maybe I won’t as the only browser selection it allows is IE 5.01 through 8.0 which I don’t use.
(:AGY)