Well I see Zango has got some great liars (or rather, truth-coverers) employed.
What Zango does basically is look at what you're doing on the internet and make pop-ups targeted at you. They bundle it with lots and lots of software so that most people will at one point or another get it on their computer. It's annoying, borderline illegal, and mean because they prey on people who don't know a lot about computers.
It is also not anywhere near things like limewire or P2P, which are mostly safe if you have proper antivirus and are smart on them ( i.e. don't download viruses yourself, make sure what you're downloading is not an .exe, or anything)
So yes, Zango may not gather any personal data (something I don't actually believe, I think it does.) but it is just adware and it is incredibly hard to uninstall. My mother recently got it on her computer and when you try to uninstall it, it goes through many screens like "Are you sure you want to uninstall?"
So avoid Zango, even if it is not as harmful as a virus or spyware.