Long-trusted software site MacUpdate has apparently gone the way of its competitors: It has been tainted by adware. A Twitter user tried to download a Skype Installer package from the site and discovered that all was not as it appeared. The file looks normal at first and when opened you're prompted with a user agreement that people generally just click past, but it's here that gives the installer the right to change browser settings and add a "search-assist" browser extension. This type of software-trickery is identical to those used by InstallCore adware and as soon as the Skype agreement is confirmed, an InstallCore browser is added to Safari. It's usually wise to download software from the developer's site but the appeal of MacUpdate was that it acted like a one-stop-shop of sorts, carrying with it a strong reputation for reliable downloads. Now, with this news coming to light, maybe it will have to be added to the boycott list right under Download.com and Softonic.