IPAddress server(173,194,33,104); // Google
char serverName[] = "en.wikipedia.org"; // twitter URL
If you are going to change the code, changing (or removing) the comments would be good, too.
The Arduino forum is php based, and doesn't redirect all over the place like wikipedia does. You might try accessing a forum topic, and see what response you get.
The "connection failed" message is a failure to connect to the server, not a failure to get a page from the server.