I guess I'll chime in.
Stand-alone media players cost less than $100, sit there on the network, have zero moving parts, and don't have a lot of power dissipation. Connect it to your HDTV (Or 1080p capable LCD monitor) and use it for what it does -- play media. A purpose-built Mini-ITX PC with an IR remote and enough processor and video to playback 1080p Hi10p media costs considerably more than $100, and then it becomes tempting to use it for other unrelated things. It's definitely going to use more power, which means more heat, which means ventilation, particularly if you want it quiet, which means LOTS of ventilation for passive cooling.
My main concern though is that Hi10p support doesn't even seem to be on the radar for the stand-alone media players. I see mention of it on things like the WDTV forums. People with the ASUS O!Play devices (like me) aren't even bothering to ask, because we know that it's just not going to happen. (Which is a shame, because I get really nice playback of other 1080p x264 media from the device.) Now that the Matroska header compression thing is sorted out in the firmware, I quite like it.
Hi10p is definitely not automatically better, and makes certain watching choices impractical. In this case,
Another system I have just doesn't have the grunt on its own. With CoreAVC (v2.6) codec, it can handle 1080p x264 reasonably well, with it only glitching on really high compressed areas. As such, I was happy with it. I am NOT going to spend money on upgrading the video card, or in fact anything on that machine. When its time comes, I'm going to hit the HDD with a hammer and junk it. (Probably save the BD-ROM drive and HD tuner that's in it for the next one.) It's the main media player for the living room. It can muddle through MOST Hi10p x264 720p media with minimal lag, but 1080p... Nope. Maybe if I didn't have to deal with Windows overhead (Since a Linux BD player is still vapourware) but as is, it's not going to work. For now, this means that I can't watch this stuff from the couch. This is also where the best sound system is at the moment, at least until I get the rest of the projector system finished.
The machine connected to my projector works just fine. No problems there. Similarly my main machine is also good.
The one is only a matter of time until I have to upgrade the machine for one reason or another, dead processor, mobo, RAM, whatever. At that time, I'll probably shuffle one of my current higher end systems into that duty, and then replace that with something hotter, which is what I usually do. This still leaves me out of watching Hi10p releases in the most comfortable watching environments in the house.
My current solution? Re-encode the video in 8-bit. It's time consuming, but since I get the re-encode started as soon as I finish downloading, doesn't tend to hold me back long, but it's a pain, and then I can't seed the downloads later unless I keep both versions.
Oh, and I've yet to find encoding problems with my re-encodes, like macro blocking, dot crawl or banding -- that wasn't there in the original -- and most of my filesizes are similar, if not smaller. Only a few are a couple of percentage points bigger.