I decided I would early bird this system and throw Ubuntu 14.04 LTS onto it and see what happened. I should mention that I don't have the quadHD+ configuration. 

During the installation you need to select the checkbox to install 3rd party software to get the wireless working.

Once installed I found that the touchpad was twitchy so I went ahead and did an apt-get update and upgrade which installed a newer kernel version (3.16.xx I believe). This seemed to fix the touchpad issues. 

The next issue I've run into on 14.04 LTS is that the audio work intermittently. I tried installing Realtek drivers without any success so I went ahead and upgraded to Ubuntu 14.10. Unfortunately 14.10 has the same issue with the audio card not being detected. I'd suggest following this post to see how things progress on the no audio front.

I did run into some issues with bringing the system out of hibernate and sleep modes however I never use them so I disabled those options. 

There is a small issue where a previously depressed key on the keyboard will get "software stuck" and repeat until you hit another key (this doesn't happen very often). The touchpad does not disable while typing either.

Overall this system runs Ubuntu 14.04 and 14.10 well out of the box as long as you don't mind not having audio and running into other quirks as listed above. 

I've heard rumblings that Dell is working on a newer version of Sputnik and will be releasing it soon (figures crossed).

If you have any other questions just let me know and I'll see what I can test for you. 

Thanks!

Thanks for testing it out! 

I couldn't wait either for de developer edition (would not be running Ubuntu anyway) so waiting for my QHD version. Can you tell me what wifi card you have? Did wifi work out of the box?

Over here (Netherlands) we can choose the wifi card. The DW 1560 or INTEL AC 7265 but on US site it does not mention which one it has.

Can you please confirm the following:

1. The dreaded "coil-whine" issue is fixed (AFAIK it is not a fanless system, but hopefully the fans are noiseless now)

2. The non-touch screen version is glossy or matte?

I'm trying to assess which is the better buy for me, this or the HP Folio 1020G1 (which is fanless and has a matte screen - and HPs usually have great Linux support), or the new MBA (if and when it comes out).

I'm sure the audio and other software problems you mentioned will be fixed eventually, when the official Linux support is released. But the screen and the fan problems are much harder to fix, if at all...

Advation: thanks for the info, this sounds promising! And the new XPS 13 (not the linux version) is already available in the UK*. That only makes me wonder if there are going to be hardware differences between the Windows and the Linux versions...

*Edit: I can only see the glossy touch screens on Dell's UK page. Too bad.

BUTABEKA: Not a problem! It's too bad the UK store doesn't have the 1920x1080 screen. I would hope they make that available soon. 

BUTABEKA: This is my first XPS 13 series system so I don't have a good comparison to older models. I do know the previous XPS 13 model (9333) had a high pitched whine that seemed to come from the keyboard when the backlight for the keyboard was on. This is not the case with the new system. A good friend of mine did have the 9333 model and was able to resolve that white issue with Ubuntu updates I believe. The fan on this system does kick on and is definitely audible, however, it does not seem to whine even when taxing the GPU. I've also noticed that the aluminum bottom definitely helps dissipate the heat which is pretty nice (Doesn't get very warm even when the system is taxed).

The LCD is matte on the 1920x1080 screen and is pretty bright. I've used it in some fairly bright areas and haven't experience any noticeable "glare" issues.

Hope this helped!

TIMDJ: I have the Dell Wireless 1560 card. It's a Broadcom card and does require the 3rd party firmware to be installed to get it running. You can simply check the "Install third-party software" during the Ubuntu 14.04 or 14.10 installation. 

According to this forum, the non-touch version will be available no sooner than March/April in the UK (and probably the rest of Europe).

And that is still just the Windows version, no Linux in sight.

Well, if the rumours about the new MBA are true (coming in March), then we'll have good competition in the spring. HP 1020 G1 is rumored to be available in February (in the US), again, March/April seems likely in the EU. Until then, back to the gym :)

Oh how disappointing!  I'm sort of in the market right now for exactly this product.  I actually don't NEED it but I really want a new MacBookAir-esque notbook but with Linux.  Light, portable, SSD, long battery life, etc.  I guess for most people the MacBook Air fills the niche.  I guess I could seek out an older model of the Ubuntu XPS Dev edition, right?  

Just wanted to update anyone looking at or following this thread that that the new XPS 13 received the Developer Edition treatment on April 9th.

The announcement blog post: http://bartongeorge.net/2015/04/09/4th-gen-dell-xps-13-developer-edition-available/. They were thankful enough to also include instructions in that blog post for installing Ubuntu and other linux distributions on the regular XPS 13s with Windows preloaded.

You can purchase an XPS 13 Developer Edition here: http://www.dell.com/us/business/p/xps-13-linux/pd. This XPS 13 is priced $50 less than similarly specced Windows XPS 13s, so this awesome piece of hardware also avoids the Windows tax.