Well what you do is you select "Connect to Server" from the file menu in 11.04 and enter your login details for the ftp server and voila.How useful is it? Its come as a default program on the Ubuntu OS?
I find it much easier than Filezilla, because of the fact that it's just like if the files were on your computer, you can do just about everything with them. I can connect in a couple seconds and edit a file in the text editor, save it, and my changes are reflected instantly, whereas with Filezilla I have to download the file, edit it, and then reupload it.
Some people may prefer Filezilla for its extra features such as bandwidth limiting, but I like using Ubuntu's file manager.