By default? No! But we have somewhere in your user settings an option that gives you the choice if new links should be open in a new tab or not. As far I know it's not build in for trending, so it's probably not working there. But on the other hand, if you want so. I think a javascript solution would be better, because:
a) It's your choice. So use your own hardware power to do it.
b) It's much easier for coders, because we don't need to put a function or check over every link.
javascript code
var target = openBlank ? "_blank" : "_self";
var links = document.links;
for (var i=0; i < links.length; i++)
{
if (links[i].href.search("coh2.org") == -1)
c[i].target = target;
}
So if another coder is faster than me, feel free to build the js solution in.