i've streamed stuff DLNA to my tv from my pc, wired, and it does not compare in quality if you just use HDMI out.
i've tried streaming both directly to my tv, and to my ps3 hooked to my tv. the tv software was complete crap. this is on a panasonic st50. i tried it once and that was enough. constant dropouts, freezes, etc. the ps3 playback was a million times better.
that said, the ps3 playback still isn't as good as just hooking up a laptop directly. you have to have it transcode on the fly, which can work just fine. however if you want to rewind or skip forward, good luck with that. it will either be really slow, or flat out lockup sometimes.
and remember, this is over wired. personally i wouldn't bother with streaming if you have the option to hook up an hdmi to it from the laptop. my tv is wall mounted and has a side hdmi slot on it, so i've used that to hook my laptop up to my tv.
just my experience and 2 cents.