I like to play youtube on my Samsung TV, but to do that via DLNA, I had to first download the video to my phone first. After that I could stream DLNA to my TV. Today I found a free app that will let me stream youtube and other video site directly to the TV without downloading it first. It is twonky beam! It works pretty well and even HD video doesn't buffer. And it is free. 
PS. My TV actually has youtube app, but it is not easy to use when searching for things.
PS. My TV actually has youtube app, but it is not easy to use when searching for things.