I finally got my RPi a few weeks ago but have not had the time to play with it until now.
The first mistake I made was trying to power it from one of it's two standard USB ports (as I did not have a mini-USB power adapter at the time). This appeared to work, in that the RPi powered up and gave some video on the HDMI connection. However, the RPi kept crashing and rebooting and the USB keyboard did not work.
I was getting very frustrated until I tried a new mini USB charger (ordered from Amazon) - now it works well and does not crash.
Next, I tried Debian Wheezy, but I found it very slow - even for gmail browsing, and I could not find any instructions that worked to get YouTube working.
Finally, I tried an XBMC build from
http://wordpress.silenz.se/ and then found a guide on how to install BBC iPlayer and other TV add-ins. I also found that a TVCatchup add-in is also available, so I can watch Live UK TV as well! Picture quality varies and there is some buffering delay on occasion even though I have a direct Enet connection.
It is ironic that TVCatchUp plays live TV, whereas as BBC iPlayer and other TV players play recorded TV!
My next step is to get a WiFi dongle working and then an IR dongle for a remote mini-keyboard.