We just got the new XLites in at the store I work at. I haven't seen anyone post the weight of their XLite regular without the stuff sack so I figured I would. I weighed 3 of them and they were 12.6, 12.7 and 12.8 oz so there's some variation on my, admittedly, not the greatest scale.
I heard about the tapered Neo Airs this summer after someone I was hiking with called Thermarest about their leaky pad. I've been so excited to see one and was planning to buy it when they came out but now that I've seen them I'm pretty disappointed. I haven't had much experience with the original but the new pads seem way too delicate. All three pads had bubbles in the seam connecting the valve to the pad. The one I inflated held fine but it made me nervous. The fabric seems really thin and felt more like plastic than fabric to me. It is very noisy as well, especially when rolling it up. You would be hated by your campmates if you were packing up early in the morning (say in a shelter along the AT). I'm afraid the noise, price and concerns about durability have turned me off this pad.