OK, here is my take on Baytrail, FWIW.
Got an ASRock Q1900-ITX with 4Gig of RAM to replace a very old VIA C7 board
inside a Serener GS-L02 heatpipe case
. This case was specifically designed for that VIA board, so I planned on modifying the heatpipes. Long story short: Did not work out, as the RAM has to be in the slot, which is in the path of the heatpipes, otherwise it would not boot. ATM I'm running it inside this case with the stock heatsink on. Using an already existing X25-M 80GB SSD.
Gave up on Linux pretty soon, will try again in about 2 years if GPU support has arrived in the Kernel (was like this with the VIA board). Installed win7 for now.
I'm amazed. This board finally is, what I expected the VIA board to be (in 2008). When doing office, internet, multimedia I can feel no difference to my big and hot FX-8120 setup. Idling it takes 13-14W from the wall.
Just for fun I installed two games to check out the weakish GPU. Osmos runs just fine (causing 100% GPU load at 1920*1080), Trackmania is playable with 40FPS at 1280x768 (no AA etc.). Of course this is mere theory. Anybody looking for a gaming setup will get something else.
The CPU keeps just stunning me. For instance: Handbrake transcodes a DVD to mp4 with 65FPS. Sure, the FX-8120 manages 180 FPS, but hey, it's CPU package alone consumes 116W, while the J1900 lives on a meagre 2,9W while transcoding.
Playing video (DVD material in mp4) makes no difference when using win media player (1-5% CPU load, same as in idle, 10% GPU), VLC player takes ~12% CPU and 19% GPU. Can't check out Blueray.
The temps while transcoding go up to 77° when the case is closed (being a heatpipe case, there are absolutely no holes) compared to 66° when open. The CPU runs at 2,4GHz all the time, no throttling. At light loads the temps stay below 60° in the closed case. So I wonder, if I should bother at all, trying to find a heatpipe solution (I would have to buy a heatpipe block and two pipes).
All I can say, as a mere workstation it's more than adequate and dirt cheap. Board+RAM cost me € 112,- (and I could have gone cheaper, but there is a good B&M dealer around here, I want to support them), I wonder how much I would have had to spend if I I had gone the NUC way. A 2820 NUC sells for €110,- around here. Without RAM.
Throw in a 128GB MX-100 and an ITX case for ~40,- and anybody looking for casual everyday PC could get this for a little over €200,-
IMHO that's impressive.