I just purchased one and I am very happy. Indeed it is the best portable laptop I have every owned. I have a larger desktop replacement Windows laptop, super powerful Windows PC and a self-modified Mac Pro I use for various heavy lifting tasks. Interestingly, I can access my heavy lifting machines remotely easily (and smoothly) with my new MacBook if necessary. It is light, gorgeous (making light to medium computational work much more enjoyable compared to most laptops), and it blows my 2008 aluminium unibody MacBook which was upgraded to a SSD and 8GB of ram out of the water. Still a great machine though. Due to the expense of this new MacBook I suggest great protection unless money is not important to you or you think you are a God incapable of dropping the darn thing or having it get scratched in your brief case. I have opted for a G-Form impact protection sleeve and a Moshi hard shell. I think I could still experience damage in the future, but these items should reduce the probability of minor damages.
I find the single port fun (I like finding nifty cables and adapters), the new keyboard is useful and the FaceTime camera with low resolution does not bother me as I can use my iPhone, iPad or MacPro for important FaceTime communications. Having low resolution FaceTime is better than no FaceTime on the road (e.g., if my phone dies). My perception is that this little machine can do so much, so quickly and efficiently it is hands-down the best laptop money can buy. Think about it: (1) Crazy awesome weight; (2) No fan; (3) Fast, large SSD; (4) Amazing display; (5) Exceptional build quality; and (6) OS X ecosystem and amazing wireless AC connectivity. It simply does not struggle to complete simple common tasks (e.g., word processing, web surfing, watching video). Beyond primarily being a portable consumption machine, it can produce sophisticated product (albeit a bit more slowly than a professional machine). In 5 years I can imagine a portable MacBook Pro capable of 90-95 percent of heavy lifting Windows desktop tasks but retaining the same form factor of this machine (i.e., the new MacBook). Until then I will try not to upgrade 😉