I have just received the 512Mb Raspberry Pi that I have had on order from RS Components for several months. It is running Raspbian wheezy on a 16Gb SD card.
It was very easy to get OpenRemote and my java ORControl program running on it. So I now have an always-on home automation server.
It seems a little bit slow, which causes processing of the RF messages to get behind sometimes, and also causes some error messages on the android app, but I think it will be good enough. I could run ORControl on a second Raspberry Pi.