Im not sure if this will be made available for the PS3 to host on but the PS2 has had a history of been used as servers for various things, basically because with the PS2 you can just chuck a big IDE hard drive on the back of the network adaptor, and there you have it, install linux on it, run ftp servers, webserver etc, and its about 60w of power.
The main problem is finding a server program which will work on the operating system, because things like mail, ftp, webservers etc all are so commonly used its worth people spending time developing these peices of software.
But with LFS, alot of people play but it would not be worth the develepors time converting all of their software for the playstation, mainly because you will want to use your console for other things, but also how many people would have a serious host on a playstation???
Is a much more reliable and better idea to rent a server, you can fit alot more people in than your home connection could ever handle, plus, your free to play with your new ps3 as much as you want without cutting all your players off!!