I got my Neoair Xlite small in the mail today from Backcountry.com. I thought I'd post up a few pics and some initial thoughts.
Weight: I was pleasantly surprised when I opened the box and weighed the pad and it came out to 8.3 oz, which is pretty close to the 8 oz spec. Then I unrolled it, and the stuff sack, patch kit, and product literature fell out! I was even more pleased when I re-weighed it. Total weight for the size small: 7.2 oz!
Size: It is the same length as the old Neoair small, but feels narrower because of the tapered design. I find that with NeoAirs I have to put my Kookabay pillow on top of the pad since they are so thick, and this takes up a fair chunk of the length of such a short pad. If you don't do this, you might not notice a difference since your hips will be on a wider part of the pad.
Noise: It is definitely a bit more crinkly than my old NeoAir, but doesn't bother me at all.
Warmth: I laid down on the floor on both my old NeoAir and new XLite a few times and couldn't really tell much difference. This is a pretty bad test though and I doubt I could tell the difference between 2.5 and 3.2 R value with such a simple test.
Fabric: The fabric on the old NeoAir is totally opaque. In contrast, the new Xlite fabric is partially see-thru. You can easily see the internal baffles and reflective layer inside the pad.
Valve: The valve has been relocated to the edge of the pad on the seam between the top and bottom panels with a tapered plug.
Overall I am pretty pleased. It is both 20% lighter and 20% warmer than the original. I am torn whether I should offset some of the weight savings by exchanging it for a regular size, since the small is pretty minimal with the tapered design and my pillow.