Here's a System76 review: http://ubuntuforums.org/showthread.php?t=343798
A friend says: Heard great things about system76 and I like the fact they offer matte screen options over the usual shiny pieces. I am not a fan of core and intel gma in general. Upper echelon corei7 do very well though because of all the cache they pack in there. Have you considered something like Lenovo x120? Though not a big performer, would likely get you buy and supports 1080p resolution (even on 12" models). I really dont like the resolutions on system76 systems I see (768 vertical really does affect your view space). I am currently looking at e450 models from Lenovo (130e), Asus, Dell (the only one that bundles w/ Ubuntu out of the factory), or Acer (preferred).
Again, after my experiences with Asus, I'm hesitating to buy from anyone who will ignore any problems on Linux using the excuse that it is Linux. It needs to have all driver software in the Linux tree or it didn't happen. :-)