Finally got ahold of one of these, and I am (predictably) psyched. It feels more fitted than the Boreas, especially in the sleeves. The secondary body/undersleeve/hood fabric is supposedly the same as the Boreas, but feel both lighter and quite a bit stretchier than my 2012 Boreas. Maybe that Boreas lost a bit of give after all the abuse it's had, but I think the fabric has changed. The primary shoulder and top of sleeve fabric is quite a bit burlier, and is a directional knit (i.e. the inner is textured and the outer is smooth). The primary fabric has a DWR, the secondary does not. Pockets are big, high enough to stay off your hipbelt, and lined with a single layer of nice mesh. The hood and cuffs are bound with lycra fabric, which makes the hood snug up very well. The zip ends right under the chin, and the overall sensation is identical to the Cirrus. My only disappointment is the main zip, which is a #3. I'd prefer the #5 on the Boreas and Alpine. Combined with the stretchy main fabric it won't be quite as smooth running.
Men's medium weighs 10.4 oz.
Will update with photos, numbers, and impressions from actual use as I go.