I had mine at 12+2. It's called Verifi here and they only do it for high risk pregnancies. High risk being 35 or older at time of delivery, or previous genetic problems in the family or previous pregnancies. Verifi can be done as early as 10 weeks. They cannot tell gender for twins, though they can tell you whether or not they've detected a Y chromosome, which would mean at least one is a boy, if no Y, then you've got 2 girls. My results were negative, meaning everything looked great and I am having my 3rd boy. I loved finding out as soon as possible and preferred the phone call over the scan personally.
I was told this test is 99% accurate and it is also covered by my insurance because I am high risk. Just an FYI, Verifi is only offered to high risk women and will likely one day be the standard type of First Tri screening in future. These tests are also marketed under Harmony, Panorama, MaterniT21. They are said to reduce the risk of miscarriage due to their much more accurate testing compared to the NT scan and blood test. Reducing the false positive rate will reduce the need for CVS or Amnio, therefore reducing the miscarriage risks. The abortion issue due to gender have been questioned, but I really hope that is not going to be an issue at all. Would be a shame to not get to use this brilliant technology for what it's meant for. I can only assume that if that should happen they will no longer tell you the gender, just do the chromosome testing.
I felt very fortunate to have been able to know the baby didn't have one of the syndromes that they check for in scans going on soft markers. So many of my friends and family walked around gut sick for weeks because of nuchal scan results and various soft marker test that they tested positive for and their baby ended up being fine. 
