Well here we go again. GameSpy Technology, the company running the multiplayer interface for several games including UT3 is officially going down.
What this means is that if Epic does not come up with their own solution by May 31, 2014, the server browser in UT3 will be nonfunctional. The only way to connect to your favorite server would be through direct IP and I’m assuming you would not be able to “login” to the game as normal.
The good news is that, according to THIS article, Epic is working on a their own solution. Here’s hoping they can pull that off seamlessly.